Sickle Cell Disease

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Quick Reference

RxDrug of choiceHydroxyurea (15-20 mg/kg/day, titrate to MTD)

AltAlternativesVoxelotor 1500 mg daily, Mitapivat 50-100 mg BID, L-glutamine 0.3 g/kg BID

⊘AvoidMeperidine (seizure risk), Ticagrelor (no benefit), Crizanlizumab (negative STAND trial), non-dihydropyridine CCBs (exacerbate heart failure)

DxTest of choiceHemoglobin electrophoresis or HPLC for diagnosis; TCD ultrasound for stroke screening in children

ScKey scorePhenotypic risk score (Sachdev), predicts 4-year mortality using TRV, echocardiographic parameters, BMI, BUN, alkaline phosphatase, heart rate, age

→When to referRecurrent VOC despite hydroxyurea, acute chest syndrome, stroke, priapism, progressive organ damage, consideration for HSCT/gene therapy

Early diagnosis via newborn screening, hydroxyurea as first-line disease-modifying therapy, and systematic surveillance for end-organ damage reduce morbidity and mortality; curative options (HSCT, gene therapy) should be discussed early for severe disease.

Sickle cell disease (SCD) is an inherited hemoglobinopathy caused by a point mutation in the β-globin gene (Glu6Val) that produces hemoglobin S (HbS), which polymerizes under deoxygenation, leading to chronic hemolytic anemia, recurrent vaso-occlusive events, and progressive multi-organ damage. With an estimated 7.74 million people affected worldwide and 515,000 affected births annually, SCD imposes a substantial global burden, particularly in sub-Saharan Africa where under-5 mortality can exceed 50% without intervention. Management has evolved from supportive care to disease-modifying therapies (hydroxyurea, voxelotor, mitapivat) and curative options (hematopoietic stem cell transplantation, gene therapy). Early diagnosis through newborn screening, infection prophylaxis, and systematic surveillance for end-organ damage are critical to improving outcomes.

Overview and Recommendations

Background

•Sickle cell disease (SCD) is a monogenetic disorder caused by a single nucleotide substitution (GAG→GTG) at codon 6 of the β-globin gene, replacing glutamic acid with valine to produce hemoglobin S (HbS). Under deoxygenation, HbS polymerizes, distorting erythrocytes into the classic sickle shape and initiating a self-perpetuating cycle of hemolysis, inflammation, and vaso-occlusion that progressively damages every organ system.
•SCD affects approximately 7.74 million people globally, with 515,000 affected births annually, a 13.7% increase since 2000 driven by population growth in sub-Saharan Africa and the Caribbean. Over 75% of affected births occur in sub-Saharan Africa, where without newborn screening and comprehensive care, 50-90% of children die before age 5. In high-resource settings, median age at death for adults with SCD and chronic kidney disease is only 53 years.
•The three most common genotypes, HbSS (homozygous), HbSC (compound heterozygote with HbC), and HbSβ-thalassemia, account for 98.5% of SCD cases. HbSS and HbSβ⁰-thalassemia are typically severe, while HbSC and HbSβ⁺-thalassemia follow a milder course. Genetic modifiers such as elevated fetal hemoglobin (HbF) and co-inherited α-thalassemia reduce disease severity, while variants in BCL11A and HBS1L-MYB modulate HbF levels.
•Vaso-occlusion is a multicellular thromboinflammatory cascade: dense sickled cells adhere to venular endothelium via receptors like Lu/BCAM, P-selectin upregulation mediates leukocyte and sickled cell adhesion, and von Willebrand factor becomes hyperadhesive. Hemolysis releases cell-free hemoglobin and heme, which activate Toll-like receptor 4 and the cGAS-STING pathway, promoting neutrophil extracellular trap formation and coagulation activation. This chronic inflammation drives progressive fibrosis in kidneys, lungs, liver, and heart.
•The paradigm shift in management began with hydroxyurea (FDA-approved 1998) and accelerated with targeted therapies (voxelotor, mitapivat, L-glutamine) and curative cellular therapies (hematopoietic stem cell transplantation, exagamglogene autotemcel). The four pillars of modern disease-modifying therapy, hydroxyurea, voxelotor, mitapivat, and L-glutamine, target HbS polymerization, hemolysis, and oxidative stress, while P-selectin inhibition (crizanlizumab) showed mixed results.

Evaluation

•Suspect SCD in any patient with episodic severe pain (vaso-occlusive crisis), chronic hemolytic anemia, or a family history of hemoglobinopathy. Typical presenting symptoms include bone pain, chest pain, abdominal pain, or back pain, often triggered by cold, infection, dehydration, or stress. Ask about prior complications: acute chest syndrome, stroke, priapism, leg ulcers, or splenic sequestration.
•Examine for pallor, jaundice, scleral icterus, and splenomegaly (in children; adults often have functional asplenia). Look for leg ulcers (typically over medial malleoli), retinopathy on fundoscopy, and signs of pulmonary hypertension (loud P2, right ventricular heave). In children, assess growth parameters and neurodevelopmental milestones.
•Order a complete blood count with reticulocyte count, typical findings: hemoglobin 6-9 g/dL, elevated reticulocytes (3-15%), and elevated mean corpuscular hemoglobin concentration. Peripheral blood smear may show sickle cells, target cells, Howell-Jolly bodies (functional asplenia), and nucleated red blood cells. A normal smear does not exclude SCD.
•Definitive diagnosis requires hemoglobin analysis by high-performance liquid chromatography (HPLC), isoelectric focusing, or capillary electrophoresis. HbS >50% with another β-globin variant (HbC, β-thalassemia) confirms SCD. Molecular genotyping (PCR/sequencing) is the gold standard for equivocal cases, prenatal diagnosis, or identifying coinherited modifiers like α-thalassemia.
•In children with HbSS or HbSβ⁰-thalassemia, perform annual transcranial Doppler (TCD) ultrasound from age 2 to at least 16 years to screen for stroke risk. Abnormal TCD velocity >200 cm/s warrants chronic transfusion or hydroxyurea. A single brain MRI without sedation is recommended at least once in childhood and once in adulthood to detect silent cerebral infarcts.
•Screen for end-organ damage annually: urine albumin-to-creatinine ratio and estimated glomerular filtration rate for nephropathy; echocardiography with tricuspid regurgitant jet velocity (TRV) every 1-3 years starting in adolescence for pulmonary hypertension; dilated fundus examination yearly for high-risk patients (older HbSC males, low HbF) and triennially for low-risk patients.
•Evaluate for acute complications: in a patient with acute pain, fever, and respiratory symptoms, obtain chest X-ray and pulse oximetry to rule out acute chest syndrome (new pulmonary infiltrate plus respiratory symptoms). In recently transfused patients with pain, fever, and falling hemoglobin, suspect delayed hemolytic transfusion reaction (DHTR), check hemoglobin, LDH, reticulocyte count; reticulocytopenia is a red flag.
•Assess for venous thromboembolism: SCD carries a 5.2 events/1000 person-years incidence of VTE, with pulmonary embolism disproportionately common. Consider D-dimer and CT pulmonary angiography if clinically indicated. Also evaluate for priapism in males: ask about sustained painful erections >4 hours.
•Consider bone marrow examination only for specific indications: aplastic crisis (parvovirus B19, shows erythroid hypoplasia with giant pronormoblasts), unexplained cytopenias, or pre-transplant assessment. Routine marrow is not needed for diagnosis.
•Use validated prognostic scores to stratify risk: the phenotypic risk score (Sachdev) uses TRV, estimated right atrial pressure, mitral E velocity, left ventricular septal thickness, BMI, BUN, alkaline phosphatase, heart rate, and age to predict 4-year mortality (3% to 75%). The hemolytic component (reticulocyte count, LDH, AST, total bilirubin) independently predicts mortality (HR 3.44).

Management

•Initiate hydroxyurea as first-line disease-modifying therapy for patients with frequent vaso-occlusive crises (≥2 per year), acute chest syndrome, or symptomatic anemia. Start at 15-20 mg/kg/day orally, escalate every 8 weeks to maximum tolerated dose (MTD) defined by mild myelosuppression (absolute neutrophil count 2000-4000/μL) or plateau in HbF response. Target HbF ≥20%.
•Monitor hydroxyurea adherence with blood levels or mean corpuscular volume (MCV), undetectable drug levels occur in 61% of patients ≥10 years and 76% of those <10 years, correlating with lower MCV and HbF. Adjust dosing accordingly.
•For patients with inadequate response to hydroxyurea (persistent VOC or anemia), add or switch to novel oral agents: voxelotor 1500 mg orally once daily for anemia (Hb response 51% vs 7%, NNT=2.3); mitapivat 50-100 mg twice daily for hemolysis and VOC (Hb response 46-50%, NNT≈2.2); L-glutamine 0.3 g/kg/dose twice daily for oxidative stress (median 1 fewer crisis per 48 weeks).
•Do not prescribe crizanlizumab as first- or second-line therapy, the phase 3 STAND trial showed no significant reduction in annualized VOC rates (2.49 vs 2.30 with placebo) and higher grade ≥3 adverse events (56% vs 32%). Discuss conflicting SUSTAIN and STAND results if considering.
•For acute vaso-occlusive crisis, administer parenteral opioids within 30 minutes of triage: morphine 0.1-0.15 mg/kg IV or hydromorphone 0.015-0.02 mg/kg IV. Reassess pain every 15-30 minutes; escalate dose by 25-50% or initiate patient-controlled analgesia if severe. Avoid meperidine due to seizure risk. Use intranasal fentanyl 1.5 mcg/kg as bridging if no IV access.
•For acute chest syndrome, provide supplemental oxygen to maintain SaO₂ ≥95%, bronchodilators if wheezing, and empiric broad-spectrum antibiotics (macrolide + third-generation cephalosporin). Use incentive spirometry (10 breaths every 2 hours while awake) to reduce progression. For hemoglobin ≤9 g/dL or rapid fall, give simple transfusion 10 mL/kg packed red cells; for severe or worsening ACS, perform exchange transfusion. Transfer to ICU if SaO₂/FiO₂ ratio <310.
•For acute ischemic stroke, obtain emergency neuroimaging and initiate acute red cell exchange as soon as possible (target HbS <30%). Thrombolysis is rarely used due to frequent ineligibility. For priapism lasting <4 hours, perform intracavernosal aspiration and irrigation with or without phenylephrine; for stuttering priapism, consider sildenafil prophylaxis.
•For transfusion support, use ABO/Rh (D, C, c, E, e) and Kell-matched red cells for all patients to reduce alloimmunization. Avoid transfusion during proinflammatory events when possible (alloimmunization risk increases 4-fold). For chronic transfusion (e.g., stroke prevention), maintain HbS <30% using simple transfusion or erythrocytapheresis. Start iron chelation when serum ferritin >1000 ng/mL or liver iron >5 mg/g dry weight: deferasirox 20-40 mg/kg/day, deferiprone 75-100 mg/kg/day, or deferoxamine.
•Provide infection prophylaxis: daily oral penicillin from diagnosis until at least age 5; pneumococcal vaccination with PCV13 in infancy and PPSV23 starting at age 2; annual influenza vaccine; meningococcal and Haemophilus influenzae type b vaccines. In malaria-endemic areas, provide malaria prophylaxis.
•Refer for curative therapy (hematopoietic stem cell transplantation or gene therapy) in patients with severe disease: recurrent VOC despite optimized medical therapy, stroke, progressive organ damage, or recurrent acute chest syndrome. For children with an HLA-matched sibling donor, myeloablative HSCT offers >95% event-free survival. For patients without a matched sibling, discuss haploidentical HSCT with post-transplant cyclophosphamide or autologous gene therapy (exagamglogene autotemcel, lovotibeglogene autotemcel).
•Discharge criteria for acute VOC: pain controlled on oral analgesics, no hypoxia (SaO₂ ≥95% on room air), stable hemoglobin (within 1 g/dL of baseline), no fever, ability to tolerate oral intake, and follow-up arranged within 1-2 weeks. Ensure hydroxyurea adherence and provide written crisis action plan.

Board Review — High Yield

•HbS polymerization, The root cause of SCD; triggered by deoxygenation, inhibited by fetal hemoglobin (HbF) >15-20%.
•P-selectin, Endothelial adhesion molecule targeted by crizanlizumab; SUSTAIN trial showed 45% VOC reduction, but STAND trial failed to confirm.
•Transcranial Doppler (TCD), Annual screening in children age 2-16; velocity >200 cm/s indicates high stroke risk and need for chronic transfusion.
•Acute chest syndrome, New pulmonary infiltrate + respiratory symptoms; treat with antibiotics, incentive spirometry, and exchange transfusion if severe.
•Delayed hemolytic transfusion reaction (DHTR), Suspect when hemoglobin drops 5-14 days post-transfusion with pain and fever; reticulocytopenia is a red flag; avoid further transfusion unless absolutely necessary.
•Hydroxyurea maximum tolerated dose (MTD), Defined by mild myelosuppression (ANC 2000-4000/μL); target HbF ≥20%.
•Exagamglogene autotemcel (exa-cel), CRISPR-Cas9 gene therapy targeting BCL11A; 97% freedom from severe VOC at 12 months in CLIMB SCD-121 trial.
•Phenotypic risk score, Composite of 9 variables (including TRV, BUN, age) stratifies 4-year mortality from 3% to 75%.
•Sickle cell nephropathy, Screen with urine ACR annually; ACE inhibitors for albuminuria; distinct pathophysiology from APOL1-mediated disease.
•Functional asplenia, Present in most adults with HbSS; requires penicillin prophylaxis and vaccination against encapsulated organisms.

Deep Dive — Evidence Details

1. Definition, Classification & Nomenclature

▸SCD is defined by a single Glu6Val mutation in β-globin leading to HbS polymerization; classification centers on genotype (HbSS, HbSC, HbSβ-thalassemia) which predicts severity.
▸Three genotypes, HbSS/HbSβ0, HbSC, and HbSβ+, account for 98.5% of SCD cases in large cohorts [11].
▸Global prevalence exceeds 7.7 million individuals, with under-5 mortality approximately 2.1% underscoring the need for early screening and disease-modifying interventions [2,5].

HY High Yield: Remember the three major SCD phenotypes, HbSS/Sβ0, HbSC, and HbSβ+, cover >98% of genotyped cases; classification by genotype is the first step in severity stratification [11].

Sickle cell disease (SCD), also simply called sickle cell, is a group of inherited hemoglobin-related blood disorders. Sickle cell disease is caused by an abnormality in the oxygen-carrying protein haemoglobin found in r — Sickle cell disease — Sickle cell disease (SCD), also simply called sickle cell, is a group of inherited hemoglobin-related blood disorders. Sickle cell disease is caused b...Wikipedia ↗

Sickle cell disease (SCD) is an inherited hemoglobinopathy caused by a point mutation in the β-globin gene (Glu6Val) that produces hemoglobin S (HbS), a variant prone to polymerization under deoxygenation, resulting in chronic hemolytic anemia, recurrent vaso-occlusive events, and progressive multi-organ damage.

Also Called / Synonyms

Sickle cell anemia (sometimes used interchangeably for homozygous HbSS)
HbS disease
Drepanocytosis (historical term)

Classification of Major Genotypes

SCD includes several genotypes defined by the specific β-globin mutations inherited. The three most common phenotypes, HbSS (homozygous), HbSC (compound heterozygote for HbS and HbC), and HbSβ-thalassemia (HbS with a β-thalassemia mutation), together account for 98.5% of SCD cases in large genotyped cohorts ^[11]^B2b. The table below summarizes the key genotypes and their distinguishing features.

Genotype	Mutations	Typical Severity	Key Laboratory Finding
HbSS	Homozygous Glu6Val	Severe	HbS >90% on electrophoresis; HbF variable
HbSC	Glu6Val + Glu6Lys (HbC)	Moderate-severe	HbS ~50%, HbC ~50%; target cells on smear
HbSβ⁰-thalassemia	Glu6Val + β⁰ (no normal β-globin)	Severe (similar to HbSS)	HbS >80%, no HbA; microcytosis
HbSβ⁺-thalassemia	Glu6Val + β⁺ (reduced normal β-globin)	Mild-moderate	HbS 60-80%, HbA present; microcytosis

Compound heterozygotes with HbD, HbO Arab, or HbE are rarer but clinically important and follow similar sickling pathophysiology.

Clinical Significance

SCD imposes a heavy global burden. In 2021, an estimated 7.74 million people were living with SCD worldwide, with 515,000 affected births annually, a 13.7% increase since 2000 driven by population growth in sub-Saharan Africa and the Caribbean ^[5]^B2c. The disease causes substantial pediatric mortality: the global under-20 cause-specific mortality proportion is ****, with under-5 mortality estimated at 2.1% ^[2]^A1a. Even in high-resource settings, the median age at death for adults with SCD and chronic kidney disease is only 53 years (IQR 44-61) ^[15]^B2b.

The molecular basis of HbS polymerization and its downstream cellular and vascular consequences, the core mechanisms linking genotype to phenotype, are detailed in the next section.

Pearl: Global prevalence exceeds 7.7 million individuals, with under-5 mortality approximately 2.1% underscoring the need for early screening and disease-modifying interventions ^[2]^A1a^[5]^B2c.

2. Pathophysiology & Mechanism

▸Deoxygenated HbS polymerization is the root cause; HbF potently inhibits polymerization and is the target of both pharmacologic and gene-editing therapies.
▸Intravascular hemolysis releases heme and cf-mtDNA that drive TLR4, cGAS-STING, and NET-mediated inflammation, a cascade that standard sickling-focused models underemphasize.
▸Thromboinflammation and endothelial adhesion (P-selectin, VWF, Lu/BCAM) are central to vaso-occlusion; targeting these pathways has yielded the first new FDA-approved agents in decades.

HY High Yield: The vaso-occlusive crisis is a thromboinflammatory event: P-selectin blockade reduces crisis frequency by nearly half, underscoring that endothelial-neutrophil interactions are as important as RBC rigidity [18][45].

HbS polymerization initiates a self-perpetuating cycle of , inflammation, and vaso-occlusion that progressively damages every organ system ^[39]^D5^[40]^D5. The root cause is a single nucleotide substitution (GAG→GTG) at codon 6 of the β-globin gene, replacing glutamic acid with valine. Under deoxygenation, the hydrophobic valine forms pathologic polymers that distort the erythrocyte into the classic sickle shape ^[39]^D5^[44]^D5.

HbS Polymerization and Erythrocyte Sickling

The kinetics of polymerization depend on intracellular hemoglobin concentration, oxygen tension, and the presence of fetal hemoglobin (HbF), which potently inhibits polymer formation ^[24]^D5^[44]^D5. When HbF occupies >15-20% of total hemoglobin, polymerization is substantially blunted ^[24]^D5^[48]^D5. Sickling is initially reversible upon reoxygenation, but repeated cycles cause permanent membrane damage, cation dyshomeostasis, and dehydration, producing dense, irreversibly sickled cells that are rigid and fragile ^[39]^D5^[40]^D5.

Hemolysis and the Heme-Inflammatory Axis

Intravascular hemolysis releases cell-free hemoglobin and heme into plasma. Heme acts as a proinflammatory damage-associated molecular pattern (DAMP) that activates Toll-like receptor 4 (TLR4) on macrophages and endothelial cells, shifting macrophages toward a proinflammatory phenotype that impairs efferocytosis and prolongs tissue damage ^[29]^D5. Heme binding to the newly identified receptor HCAR2 (hydroxycarboxylic acid receptor 2) triggers a negative feedback loop through heme oxygenase-1 (HO-1) induction, providing tissue protection ^[32]^D5. Concurrently, circulating mitochondrial DNA (cf-mtDNA) from sickled erythrocytes activates the cGAS-STING pathway in innate immune cells, promoting neutrophil extracellular trap (NET) formation ^[20]^B3b^[50]^B2b. NETs expose tissue factor and histones, amplifying coagulation and endothelial injury ^[50]^B2b^[58]^D5. Hemolysis also depletes nitric oxide (NO) bioavailability, as free hemoglobin scavenges NO 1000-fold faster than intra-erythrocytic hemoglobin ^[42]^D5; this NO consumption drives vasoconstriction, endothelial dysfunction, and pulmonary ^[39]^D5^[42]^D5.

Vaso-Occlusion and Thromboinflammation

Vaso-occlusion is a multicellular process. Dense sickled cells adhere to the venular endothelium via receptors such as Lu/BCAM, which is activated by oxidative stress in the absence of phosphorylation in mature dense RBCs ^[47]^B3b. P-selectin upregulation on endothelial cells and platelets mediates rolling and adhesion of leukocytes and sickled cells, the critical initiating step of vaso-occlusion ^[18]^A1b^[45]^D5^[46]^D5. The monoclonal antibody crizanlizumab targets P-selectin and reduces pain crisis rates by 45% ^[18]^A1b. Von Willebrand factor (VWF) becomes hyperadhesive during vaso-occlusive crisis (VOC), with increased high-molecular-weight multimers that promote microvascular plugging; this correlates with neutrophil activation and occurs without profound ADAMTS-13 deficiency ^[60]^B2b. Coagulation is chronically activated: thrombin generation is elevated, and high-molecular-weight kininogen (HK) cleavage is increased, contributing to early mortality and kidney injury in murine models ^[59]^D5.

Oxidative Stress and Metabolic Reprogramming

Oxidative stress in SCD is driven by hemoglobin Fenton chemistry, secondary activation of NAD(P)H oxidase and xanthine oxidase, and mitochondrial electron leak ^[33]^D5. The antioxidant defense system is overwhelmed: superoxide dismutase (SOD), catalase, and glutathione peroxidase all show decreased activity ^[33]^D5. A common SOD2 missense variant (V16A) present in ~45% of African-ancestry individuals associates with increased sickle complications ^[33]^D5. Metabolomic studies reveal hypoxic metabolic reprogramming in erythrocytes that shunts glucose toward glycolysis and the pentose phosphate pathway, increasing 2,3-bisphosphoglycerate and further reducing hemoglobin oxygen affinity ^[34]^D5. An impaired Lands' cycle (membrane phospholipid remodeling) also contributes to sickling and inflammation ^[34]^D5. Ferroportin inhibition (e.g., vamifeport) reduces sickling and hemolysis, attenuating cardiopulmonary dysfunction in sickle mice ^[36]^D5.

End-Organ Damage: A Shared Final Pathway

Repeated ischemia-reperfusion injury, microvascular occlusion, and chronic inflammation culminate in progressive fibrosis in the kidneys, lungs, liver, and heart ^[39]^D5^[41]^D5^[42]^D5. Liver sinusoidal endothelial cells (LSEC) take up free hemoglobin via macropinocytosis, leading to iron overload, senescence, and perpetuation of liver injury ^[49]^D5. In the kidney, genome-wide association studies identify SCD-specific nephropathy loci (CRYL1, VWF, ADAMTS7) independent of APOL1, suggesting a distinct pathophysiology ^[21]^B2a. The interplay of hemolysis, hyperviscosity, and vaso-occlusion determines retinal disease: HbSS patients develop maculopathy from hemolysis, while HbSC patients develop peripheral retinopathy from hyperviscosity ^[48]^D5.

Genetic Modifiers and Phenotypic Heterogeneity

Non-coding variants explain much of the phenotypic variability beyond the primary mutation. Cis-acting variants in the β-globin cluster (HBG2 promoter XmnI polymorphism) and trans-acting quantitative trait loci (BCL11A, HBS1L-MYB) modulate HbF levels and disease severity ^[24]^D5^[53]^D5^[61]^D5. Somatic mutations causing clonal hematopoiesis (CH) are more prevalent in SCD and may increase susceptibility to myeloid neoplasia, particularly after curative cellular therapies ^[67]^D5. Epigenetic age acceleration, measured by newer DNA methylation clocks (GrimAge, DunedinPACE), is detectable in adults with SCD, reflecting accelerated cellular aging from chronic inflammation ^[37]^C4.

Pearl: Vaso-occlusion is not simply erythrocyte stasis but a multicellular thromboinflammatory cascade, blocking P-selectin with crizanlizumab prevents crises, and targeting heme scavenging (hemopexin) or HCAR2 signaling may open new anti-inflammatory avenues ^[18]^A1b^[32]^D5.

Key Molecular Pathways in Sickle Cell Disease Pathophysiology

Pathway	Initiating Event	Key Mediators	Consequence	Therapeutic Target
HbS polymerization	Deoxygenation (low pO2)	HbS tetramer, HbF (inhibitor)	RBC sickling, hemolysis	Voxelotor (HbS polymerization inhibitor) ^[19]^A1b
Hemolysis-inflammation	Cell-free Hb, heme, cf-mtDNA	TLR4, HCAR2, cGAS-STING, NETs	Macrophage dysfunction, endothelial injury, coagulation	Hemopexin, HCAR2 agonists ^[29]^D5^[32]^D5
Vaso-occlusion	Endothelial/platelet activation	P-selectin, VWF, Lu/BCAM, neutrophils	Microvascular occlusion, pain, ischemia	Crizanlizumab (anti-P-selectin) ^[18]^A1b
Oxidative stress	Hb auto-oxidation, mitochondrial leak	SOD2, NAD(P)H oxidase, xanthine oxidase	Membrane damage, NO depletion	Antioxidants, SOD2 modulation ^[33]^D5
Coagulation activation	Tissue factor, NETs, hemolysis	Thrombin, HK, VWF, ADAMTS-13	Venous thromboembolism, stroke	Anticoagulants (investigational) ^[58]^D5^[59]^D5
Hepatic damage	HbS uptake by LSEC	LSEC senescence, iron overload	Progressive liver injury	Ferroportin inhibition ^[36]^D5^[49]^D5

3. Epidemiology, Etiology & Risk Factors

▸SCD affects 7.74 million people globally, with 515,000 new births annually, concentrated in sub-Saharan Africa.
▸Genotype (HbSS highest risk), alpha thalassemia (protective), elevated HbF (protective), sickle cell trait (VTE risk), and asthma (ACS risk) are the key modifying factors.
▸VTE incidence is 5.2/1000 person-years in adults, with cumulative 11.3% by age 40; VTE doubles mortality risk.

From the polymerization-driven vaso-occlusion and described above arises a disease whose global burden reflects its genetic origins and environmental modifiers. Sickle cell disease (SCD) is among the most common monogenetic disorders worldwide. In 2021, 515,000 (95% UI 425,000-614,000) babies were born with SCD globally, a 13.7% increase since 2000, and 7.74 million (6.51-9.2 million) people were living with the condition ^[5]^B2c. Over 75% of affected births occur in sub-Saharan Africa ^[31]^D5. Without newborn screening and comprehensive care, 50-90% of affected children in Africa die before age 5 years ^[31]^D5. In high-income settings, survival into adulthood is now routine, but morbidity remains substantial: a French nationwide study identified 22,619 patients, with vaso-occlusive crisis rates of 86.3 per 100 person-years ^[97]^B2c, and a Brazilian cohort reported a VOC hospitalization incidence of 812 events per 1000 person-years ^[114]^B2b. Temporal trends show a 41.4% rise in global prevalence from 2000 to 2021, driven by population growth in high-birth-rate regions ^[5]^B2c.

Genotype, Modifiers, and Clinical Risk Factors

Disease severity varies markedly by genotype. Individuals with HbSS or HbSβ⁰-thalassemia (sickle cell anemia) experience the highest complication rates, while HbSC disease and HbSβ⁺-thalassemia follow a milder course. Key modifying factors and risk associations are summarized in the table.

Risk Factor	Comparison	Odds Ratio / Relative Risk (95% CI)	Evidence Level
HbSS/HbSβ⁰ vs HbSC/HbSβ⁺	Genotype severity	OR 4.49 (2.35-8.57) for postpartum complications ^[103]^C4	4
Alpha thalassemia (co-inherited)	Presence vs absence	Protective: lower albuminuria prevalence ^[99]^B2b	2b
Elevated fetal hemoglobin (HbF)	Per % increase	Protective: reduces VOC rate ^[95]^D5	5
(SCT)	SCT vs wild-type	VTE: OR 1.8 (1.2-2.9); PE: OR 3.9 (2.2-6.9) ^[72]^B3b	3b
Asthma	Comorbidity	Increased ACS risk; HR for earlier death ^[88]^D5	5
High hemolytic component	Highest vs lowest quartile	Death: HR 3.44 (1.2-9.5) ^[101]^C4	4
Hypoxia in pregnancy	Present vs absent	Postpartum VOC: OR 4.95 (1.86-13.23) ^[103]^C4	4

Venous thromboembolism (VTE) is a major acquired risk: incidence is 5.2 events/1000 person-years among adults with SCD, with a cumulative incidence of 11.3% by age 40 years ^[111]^B2b. Pulmonary embolism is disproportionately common, and VTE confers an adjusted mortality HR of 2.32 (1.20-4.46) ^[111]^B2b. Pooled meta-analytic prevalence estimates include pulmonary 30% (95% CI 26-34), VTE 13% (9-18), and cardiac involvement 24% (17-33) ^[12]^A1a.

Seasonal and Environmental Variation

Vaso-occlusive crises increase during periods of infection, dehydration, and extreme temperatures. In malaria-endemic regions, acute Plasmodium infection triggers hemolysis and VOC, and malaria-attributable bacteraemia accounts for an estimated 62% of invasive bacterial disease in children with SCD ^[81]^B3b. Influenza and pneumococcal seasons also correlate with acute chest syndrome peaks. These associations underscore the importance of vaccination (e.g., PCV13, which shows 83.8-91% effectiveness against invasive pneumococcal disease in SCD ^[113]^B2a) and malaria prophylaxis in endemic areas.

Health Disparities

Inequities in access to care profoundly shape outcomes. In sub-Saharan Africa, most children lack newborn screening, hydroxyurea, and safe transfusion ^[31]^D5. Haitian children with SCD are significantly more anemic, malnourished, and under-immunized than their counterparts who immigrated to the United States ^[112]^B2b. Structural racism and stigmatization further compound morbidity ^[85]^D5.

Pearl: SCD is the most common monogenetic disease in the world, with >75% of the 515,000 annual affected births occurring in sub-Saharan Africa, and without early intervention, up to 90% of these children die before age 5, a preventable tragedy that makes newborn screening and basic prophylaxis the highest-yield global health interventions in SCD.

4. Clinical Presentation

▸Acute vaso-occlusive crisis is the hallmark presentation, but delayed hemolytic transfusion reaction (DHTR) mimics VOC and must be considered in recently transfused patients.
▸Cognitive dysfunction, particularly processing speed and memory deficits, is common in adults and correlates with brain infarcts and vasculopathy.
▸Genotype (HbSS vs HbSC) and genetic modifiers (α-thalassemia, HbF loci) produce distinct complication profiles: HbSS has more acute events, HbSC more chronic ocular and pulmonary disease.

HY High Yield: In any recently transfused SCD patient with acute pain and fever, check hemoglobin, LDH, and reticulocyte count, a drop in hemoglobin with low reticulocytes suggests DHTR, not simple VOC [121,140].

From the global burden of sickle cell disease, the clinical phenotype emerges through a lifetime of vaso-occlusive and hemolytic events, with severity modulated by genotype, genetic modifiers, and environmental exposures ^[40]^D5^[61]^D5^[136]^B2b.

Presenting Symptoms

Acute vaso-occlusive crisis (VOC) is the hallmark, presenting with severe pain in bones, chest, abdomen, or back, often preceded by triggers such as cold, wind, infection, or dehydration ^[136]^B2b^[137]^D5. Pain typically progresses over hours to days, with a nadir at 2-4 days. Chronic pain affects a substantial proportion of adults, with pain interference scores averaging 3.12-3.15 on a 0-10 scale ^[117]^A1b. Acute chest syndrome (ACS) presents with new respiratory symptoms, fever, and pulmonary infiltrate; it may develop during hospitalization for pain ^[127]^D5. Delayed hemolytic transfusion reaction (DHTR) mimics VOC with severe bone pain, fever, and profound anemia (median hemoglobin 49 g/L), occurring a median of 8 days after transfusion ^[121]^C4^[140]^C4.

Neurological Examination Findings

Cognitive dysfunction is a hallmark, with deficits in processing speed (58%), short-term memory (34%), and working memory (24%) in adults with neurological morbidity ^[133]^C4. Brain infarcts are found in 56% of such patients, and intracranial vasculopathy in 49% ^[133]^C4. Overt stroke presents with acute focal deficits; silent cerebral infarcts are detected on MRI. Transcranial Doppler screening identifies children at risk for stroke (see Section 5). Orbital involvement, though rare, presents with periorbital edema (100%), proptosis (64%), restricted ocular motility (57%), and reduced visual acuity (28%) ^[145]^C4.

Phenotypic Variants

Variant	Key Features	Frequency
HbSS	Most severe; more frequent VOCs, higher , earlier organ damage	~60-70% of SCD in African descent
HbSC	Milder acute course; higher risk of ocular and pulmonary chronic complications	~20-30%
HbSβ⁰-thal	Similar to HbSS	Variable
HbSβ⁺-thal	Milder, variable	Variable

HbSS patients experience more VOCs, while HbSC patients have a higher prevalence of proliferative retinopathy and pulmonary ^[144]^B2a. Genetic modifiers such as α-thalassemia trait and HbF levels (BCL11A, HBS1L-MYB) further modulate severity ^[61]^D5.

Red Flags

Acute chest syndrome: new hypoxia, tachypnea, chest pain; declining oxygen saturation or respiratory distress → consider urgent exchange transfusion ^[127]^D5.
DHTR: hemoglobin drop >2 g/dL with pain and fever within 2 weeks of transfusion; reticulocytopenia (median 140×10⁹/L) is a warning sign ^[121]^C4^[140]^C4.
Stroke: sudden focal weakness, speech difficulty, altered consciousness; requires immediate imaging and transfusion ^[143]^D5.
Splenic sequestration: rapid splenic enlargement with falling hemoglobin; life-threatening in children.
: sustained painful erection >4 hours; risk of fibrosis.

Atypical Presentations

Depression is prevalent (35.2%) and associated with higher healthcare utilization and costs ^[135]^B2b. Autoimmune disease features (arthralgia, rash) may overlap with SCD, delaying diagnosis ^[55]^D5. Molar-incisor hypomineralisation is 3.5 times more common in SCD children, linked to vaso-occlusive phenotype ^[146]^B2b. Orbital bone infarction can mimic ^[145]^C4. Respiratory symptoms without asthma (cough, wheeze) are associated with increased healthcare utilization ^[132]^B2c.

Pearl: In any recently transfused SCD patient presenting with acute pain and fever, suspect DHTR before assuming simple VOC, check hemoglobin, LDH, and reticulocyte count; a drop in hemoglobin with low reticulocytes is a red flag for DHTR ^[121]^C4^[140]^C4.

5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling

▸Peripheral blood smear shows sickle cells, target cells, and Howell-Jolly bodies, but absence of sickle cells does not exclude SCD.
▸Bone marrow examination is indicated for aplastic crisis (parvovirus B19) and unexplained cytopenias, not for routine diagnosis.
▸Molecular genotyping (PCR/sequencing) is the gold standard for definitive diagnosis and identification of coinherited modifiers.

HY High Yield: A normal peripheral blood smear does not rule out sickle cell disease; definitive diagnosis requires hemoglobin analysis by HPLC or molecular testing.

The clinical suspicion raised by episodic pain crises, chronic anemia, and end-organ complications is confirmed through a systematic hematologic workup that begins with the and culminates in molecular genotyping. Each test in this diagnostic engine serves a distinct purpose: the smear provides immediate morphologic clues, marrow examination clarifies specific complications, flow cytometry quantifies fetal hemoglobin and stem cells, and molecular profiling establishes the definitive genotype.

Peripheral Blood Smear

The peripheral blood smear remains the first-line morphologic assessment. In homozygous HbSS disease, characteristic sickle cells (drepanocytes) are present but may be scarce during steady state and more numerous during vaso-occlusive crises. Target cells, Howell-Jolly bodies (reflecting functional asplenia), nucleated red blood cells, and marked reticulocytosis (typically 3-15%) are common. Fish-shaped erythrocytes and pincer cells are also observed in SCD and correlate with anemia severity ^[188]^C4. In HbSC disease, target cells are more prominent and sickle cells fewer; HbSβ-thalassemia shows microcytosis and hypochromia. A normal smear does not exclude SCD, and the absence of sickle cells should never be used to rule out the diagnosis.

Bone Marrow Examination

Bone marrow aspiration and biopsy are not required for routine diagnosis but are indicated in specific clinical scenarios:

Aplastic crisis (most often due to parvovirus B19): marrow shows erythroid hypoplasia with giant pronormoblasts; severe cases may progress to bone marrow necrosis and fat cerebral embolism syndrome ^[167]^B3b.
Unexplained cytopenias or suspected myelodysplasia, especially in older adults or after therapy.
Evaluation of iron stores before initiating chronic transfusion or chelation.
Pre-transplant assessment of marrow cellularity and fibrosis.

In steady-state SCD, the marrow demonstrates erythroid hyperplasia with a reversed myeloid:erythroid ratio (often >1:1). Megakaryocytes are normal. Fibrosis is absent except in advanced disease.

Flow Cytometry

Flow cytometry plays several supportive roles in SCD :

Fetal hemoglobin (HbF) quantitation: Using anti-HbF antibodies, flow cytometry measures the percentage of F-cells (red cells containing HbF). This is essential for monitoring response to hydroxyurea and other HbF-inducing agents. A rise in F-cells correlates with reduced and fewer crises.
CD34+ cell enumeration: For stem cell mobilization and collection prior to hematopoietic cell transplantation or gene therapy, flow cytometry quantifies CD34+ cells in peripheral blood and apheresis products ^[159]^C4.
Detection of RBC-bound antibodies: In suspected delayed hemolytic , flow cytometry can identify IgG or complement on red cells, aiding diagnosis ^[123]^D5.
Research applications: Flow cytometry is used to detect neutrophil extracellular traps (NETs) and circulating mitochondrial DNA, which contribute to inflammation ^[20]^B3b.

Molecular and Genetic Testing

Molecular analysis is the gold standard for definitive genotyping. DNA-based methods (PCR, allele-specific oligonucleotide hybridization, or sequencing) identify the HbS mutation (Glu6Val) and distinguish it from other β-globin variants (HbC, HbE, β-thalassemia mutations). Indications include:

Confirmation of genotype when hemoglobin electrophoresis or HPLC yields equivocal results (e.g., in newborns, after transfusion, or in rare variants) ^[177]^C4.
Prenatal diagnosis and carrier detection.
Identification of coinherited modifiers such as α-thalassemia or G6PD deficiency, which influence disease severity.
Newborn screening follow-up: Initial screening by HPLC or isoelectric focusing (IEF) is confirmed by molecular testing for abnormal results ^[164]^C4^[169]^C4.

(HbAS) is not associated with vaso-occlusive crises or exertion-related death without ; therefore, a diagnosis of SCD requires documentation of two HbS alleles (or HbS in combination with another pathogenic β-globin variant) ^[154]^B2a.

Table 1: Diagnostic Tests in Sickle Cell Disease

Test	Indication	Expected Finding	Notes
Peripheral blood smear	Initial evaluation	Sickle cells, target cells, Howell-Jolly bodies, reticulocytosis	Sickle cells may be absent in steady state; smear alone is insufficient for diagnosis
Bone marrow aspiration/biopsy	Aplastic crisis, unexplained cytopenias, pre-transplant	Erythroid hyperplasia (steady state); erythroid hypoplasia with giant pronormoblasts (parvovirus B19)	Not routine; reserved for specific complications
Flow cytometry (HbF)	Monitoring hydroxyurea therapy	Percentage of F-cells	Rise in F-cells indicates response
Flow cytometry (CD34+)	Stem cell mobilization	CD34+ cell count in blood/apheresis	Essential for transplant/gene therapy planning
Molecular genotyping (PCR/sequencing)	Definitive diagnosis, prenatal testing, equivocal results	HbSS, HbSC, HbSβ-thal, etc.	Gold standard; identifies coinherited variants

Pearl: A normal peripheral blood smear does not rule out sickle cell disease; definitive diagnosis requires hemoglobin analysis by HPLC or molecular testing. Bone marrow examination is reserved for aplastic crisis or unexplained cytopenias, not for routine diagnosis.

6. Staging, Risk Stratification & Prognostic Scoring

▸Validated prognostic scores in SCD include the phenotypic risk score (9 variables, 4-year mortality 3-75%), the HCT risk score (age + donor type, 3-year EFS 57-92%), and the hemolytic component (HR 3.44 for mortality).
▸Key modifiable risk factors: HbF level, TCD velocity, NT-proBNP, albuminuria, and TRV, each guides specific interventions (hydroxyurea, transfusion, pulmonary hypertension therapy).
▸Genetic modifiers (α-thalassemia, UGT1A1, BCL11A, HBS1L-MYB) and emerging biomarkers (cf-mtDNA, sEPCR, mitochondrial genome variations) refine risk stratification but require further validation before routine use.

HY High Yield: The phenotypic risk score [205] is the most practical bedside tool for adults, calculate it once at baseline and repeat annually; a score placing a patient in the highest-risk stratum (predicted 4-year mortality 75%) should trigger immediate referral for transplant evaluation or novel therapy.

With the diagnosis established, the clinician must now stratify risk, a step that determines whether a patient is a candidate for disease-modifying therapy, chronic transfusion, or hematopoietic cell transplantation. Sickle cell disease is uniquely suited to score-driven prognostication because its clinical trajectory is shaped by a combination of hemolytic rate, end-organ damage, and genetic modifiers that can be quantified at the bedside.

Validated Prognostic Scores

Several composite scores now outperform individual clinical judgment. The phenotypic risk score developed by Sachdev et al. in a prospective cohort of 600 adults uses nine readily available variables, tricuspid regurgitant velocity (TRV), estimated right atrial pressure, mitral E velocity, left ventricular septal thickness, body mass index, blood urea nitrogen, alkaline phosphatase, heart rate, and age, to stratify patients into four groups with 4-year mortality rates of 3%, 11%, 35%, and 75% (bias-corrected C-statistic 0.763) ^[205]^B2b. This score captures the summation of cardiopulmonary, renal, and hepatic end-organ damage.

For patients considering curative therapy, the hematopoietic cell transplant (HCT) risk score by Brazauskas et al. (n = 1425) predicts event-free survival using only age and donor type. Patients ≤12 years with an HLA-matched sibling donor have a 3-year EFS of 92% (score 0); those ≥13 years with a matched unrelated donor or any age with a haploidentical/mismatched donor have a 3-year EFS of 57% (score 2-3) ^[193]^B2b.

The hemolytic component, a composite of reticulocyte count, lactate dehydrogenase, aspartate aminotransferase, and total bilirubin, independently predicts mortality (HR 3.44, 95%) and correlates with pulmonary , hypoxemia, and leg ulcers ^[101]^C4. A multimarker flow adhesion score combining whole-blood adhesion to P-selectin and VCAM-1 identifies patients at 5.64-fold higher risk of vaso-occlusive crisis (C-index 0.63) ^[208]^B2b. Emerging machine-learning models using retinal optical coherence tomography angiography predict 12-month hospitalization (AUROC 0.717), kidney damage (AUROC 0.881), and heart-lung damage (AUROC 0.866) ^[197]^B2b.

Key Prognostic Factors

Factor	Good Prognosis	Poor Prognosis
Fetal hemoglobin (HbF)	Higher HbF (per 1% increase, OR 0.92 for pulmonary hypertension) ^[214]^B3b	Low HbF
α-thalassemia co-inheritance	Reduces and disease severity ^[191]^B3b	Absent
Transcranial Doppler (TCD) velocity	<200 cm/s (normal) ^[204]^D5	≥200 cm/s (abnormal, high stroke risk)
NT-proBNP	<153.6 pg/mL (negative predictive value for pulmonary hypertension) ^[202]^C4	≥153.6 pg/mL (sensitivity 85.7%, specificity 94.6%)
Albuminuria	Normal urine albumin-to-creatinine ratio ^[200]^D5	>100 mg/g (predicts kidney injury)
TRV on echocardiography	<2.5 m/s ^[205]^B2b	≥2.5 m/s (associated with mortality)
UGT1A1 promoter variants	Wild-type	TA7/TA7 (increased bilirubin, cholelithiasis) ^[215]^B2b
BCL11A / HBS1L-MYB variants	HbF-elevating alleles ^[61]^D5	Non-elevating alleles

Emerging Biomarkers

Circulating mitochondrial DNA (cf-mtDNA) acts as a damage-associated molecular pattern that triggers neutrophil extracellular traps via the cGAS-STING pathway, and its levels rise during crises ^[20]^B3b. Mitochondrial genome integrity, including mtDNA copy number and heteroplasmy burden, declines with age in sickle cell anemia and correlates with mortality risk ^[201]^C4. Soluble endothelial protein C receptor (sEPCR) is elevated in patients with chronic kidney disease and may serve as a prognostic marker for sickle nephropathy ^[194]^D5.

Risk Stratification in Clinical Practice

No single score is sufficient; the clinician integrates multiple domains. In children, TCD screening is mandatory to identify those who benefit from chronic transfusion for stroke prevention ^[204]^D5. In adults, the phenotypic risk score ^[205]^B2b and hemolytic component ^[101]^C4 guide the intensity of monitoring for pulmonary hypertension, renal impairment, and early mortality. Genetic modifiers such as α-thalassemia and UGT1A1 status refine risk for specific complications ^[191]^B3b^[215]^B2b. These risk scores inform the intensity of monitoring and the threshold for acute intervention, which is discussed in the next section.

Pearl: The phenotypic risk score ^[205]^B2b is the most practical bedside tool for adults, calculate it once at baseline and repeat annually; a score placing a patient in the highest-risk stratum (predicted 4-year mortality 75%) should trigger immediate referral for transplant evaluation or novel therapy.

7. Acute & Emergency Management

▸Parenteral opioids (morphine or hydromorphone) given within 30 minutes of triage are first-line for acute VOE; a dedicated day hospital reduces time-to-analgesic and admission rate.
▸SaO₂/FiO₂ ratio <310 at ACS diagnosis triages patients for ICU transfer with high specificity (82%).
▸Acute ischemic stroke in SCD should be managed with acute red cell exchange; thrombolysis is rarely indicated.
▸Priapism requires detumescence within 4 hours; intracavernosal aspiration with sympathomimetic is first-line.

Rx Drug of Choice: First-line for acute VOE: **morphine 0.1-0.15 mg/kg IV** or **hydromorphone 0.015-0.02 mg/kg IV** within 30 minutes; intranasal fentanyl (1.5 mcg/kg) as bridge if no IV access.

HY High Yield: SaO₂/FiO₂ ratio <310 at ACS diagnosis identifies patients who need ICU-level care (sensitivity 63%, specificity 82%).

From risk stratification, the clinician is now equipped to anticipate the acute complications that dominate SCD morbidity: vaso-occlusive pain episodes (VOE), acute chest syndrome (ACS), stroke, and priapism. These emergencies demand protocolized, time-sensitive intervention to reduce pain, prevent end-organ damage, and lower mortality.

Step 1: Triage and Immediate Assessment

Upon presentation with acute pain, assess severity, oxygenation, and respiratory effort. Obtain , chest auscultation, and a fever screen. An SaO₂/FiO₂ ratio <310 at ACS diagnosis identifies patients at high risk for ICU transfer (sensitivity 63%, specificity 82%; adjusted OR 8.94, 95%) ^[228]^B2b. Parenteral access and baseline labs ( , reticulocyte count, type and screen) are obtained urgently.

Step 2: - First-Line and Escalation

The cornerstone of VOE is rapid and adequate parenteral opioid analgesia. Administer 0.1-0.15 mg/kg IV or 0.015-0.02 mg/kg IV within 30 minutes of triage ^[221]^B3b. Reassess pain every 15-30 minutes; if pain remains severe, escalate the dose by 25-50% or initiate patient-controlled analgesia (PCA). Intranasal (1.5 mcg/kg) may be used for patients without IV access as a bridging strategy ^[233]^D5. A dedicated day hospital (or SCD-specific infusion unit) reduces time to first analgesic (median 32 vs 70 minutes) and lowers admission rates from 57% to 29% compared with the general ED ^[221]^B3b ^[232]^C4.

What NOT to do: Avoid due to risk of seizures with repeated dosing; the 2022 HESTIA3 study found no benefit of over placebo for VOE prevention ^[69]^A1b, and ticagrelor has no role in acute management.

Step 3: Acute Chest Syndrome - Recognition and Respiratory Support

ACS is defined by a new pulmonary infiltrate plus respiratory symptoms (cough, dyspnea, chest pain) and hypoxemia. Immediate interventions include supplemental oxygen to maintain SaO₂ ≥95%, bronchodilators if wheezing is present, and empiric broad-spectrum covering atypical organisms. Incentive spirometry (10 breaths every 2 hours while awake) reduces progression to severe ACS. For patients with SaO₂/FiO₂ <310, transfer to a higher level of care is strongly recommended ^[228]^B2b. Simple transfusion (10 mL/kg packed red cells) is indicated for hemoglobin ≤9 g/dL or rapid fall, while exchange transfusion is reserved for severe or worsening ACS despite simple transfusion. ECMO may be considered in refractory cases; in a registry study, VV-ECMO had 61.1% in-hospital survival vs 25.5% for VA-ECMO ^[7]^B2b.

Step 4: Acute Stroke and Priapism

in SCD is a medical emergency. Obtain emergency neuroimaging and, if hemorrhagic stroke is excluded, initiate acute red cell exchange (RCE) as soon as possible. Higher post-RCE hematocrit was associated with decreased odds of death or persistent neurological symptoms (OR 0.69 per 1% increase, 95%) ^[106]^C4. Thrombolysis is rarely used due to frequent ineligibility (age, presentation timing, intracranial hemorrhage).

requires urgent detumescence within 4 hours to prevent . For acute episodes (duration <4 hours), intracavernosal aspiration and irrigation with or without instillation of a sympathomimetic (e.g., ) is first-line ^[22]^D5. Oral or intravenous fluids and analgesics are supportive. For stuttering priapism (recurrent, brief episodes), a phosphodiesterase type 5 inhibitor (e.g., ) can be considered as prophylaxis ^[22]^D5.

Step 5: Transition to Definitive Management

Once the acute event resolves, evaluate for disease-modifying therapy. (start at 15-20 mg/kg/day, titrate to 20-35 mg/kg/day as tolerated) reduces VOE frequency and improves survival in children and adults ^[223]^B3b^[220]^B3b. Adherence to hydroxyurea with average daily dose ≥1 g or proportion of days covered ≥0.80 significantly reduces 30-day readmission (OR 0.59-0.72) ^[223]^B3b. Patients with recurrent severe events should be referred for chronic transfusion therapy or evaluation for hematopoietic cell transplantation (see Section 8).

Controversies and Guideline Disagreement

Question	Position A	Position B	Strength of disagreement	Implication for practice
Timing of opioid in pediatric VOE	Early opioid ≤30 min	Delayed opioid >60 min	Mild (no difference in hospital admission; RR 0.96, 95% CI 0.85-1.10) ^[234]^A1a	Focus on adequate dosing and frequent reassessment rather than arbitrary time thresholds
Morphine prescription bias in SCD	Real-world data show inadequate analgesia for SCD patients	Standardized vignettes show higher morphine prescription in SCD vs non-SCD (90% vs 84%)	Moderate (conflicting evidence from different methodologies) ^[231]^B2b	Implicit bias may be reduced when clinical information is depersonalized; advocate for structured pain protocols

Pearl: In acute VOE, prioritize parenteral opioids within 30 minutes and reassess frequently; use the SaO₂/FiO₂ ratio at ACS diagnosis (cutoff 310) to triage ICU-level care, and treat priapism within 4 hours to preserve erectile function.

Comparison of Acute Care Settings for VOE Management

Setting	Median time to first analgesic	Admission rate	Key advantage
General Emergency Department	70 min	57%	Universal access
Dedicated Day Hospital / SCD Infusion Unit	32 min	29%	Faster analgesia, lower admission, guideline-concordant dosing

Data from ^[221]^B3b and ^[232]^C4.

8. Long-term & Definitive Management

▸Hydroxyurea is first-line disease-modifying therapy; adherence assessed by MCV or drug levels is often inadequate (undetectable in 61% of older patients).
▸Voxelotor (1500 mg daily) and mitapivat (50-100 mg BID) achieve hemoglobin responses in ~50% of patients, NNT ≈2.
▸Crizanlizumab cannot be recommended after the negative phase 3 STAND trial.
▸Refer for curative HSCT or gene therapy when disease remains severe despite optimized medical management.

HY High Yield: Hydroxyurea undetectable in 61% of HbSS patients ≥10 years despite prescription; check MCV and drug levels to confirm adherence before switching therapy.

Once acute vaso-occlusive crises are controlled and the patient is stable, the central task becomes selecting a disease-modifying regimen that reduces the frequency of painful events, attenuates , and forestalls progressive organ damage. The choice among hydroxyurea, newer targeted agents, and curative cellular therapies depends on genotype, disease severity, adherence capacity, and access to specialized centers.

Step 1: Initiate Hydroxyurea as First-Line Disease-Modifying Therapy

Hydroxyurea (hydroxycarbamide) remains the cornerstone of long-term for patients with frequent vaso-occlusive crises (≥2 per year), acute chest syndrome, or symptomatic anemia. The drug is started at 15-20 mg/kg/day orally, escalated every 8 weeks to the maximum tolerated dose (MTD) defined by mild myelosuppression (absolute neutrophil count 2000-4000/μL) or a plateau in HbF response ^[40]^D5 ^[41]^D5. The target HbF level is ≥20%, though many patients achieve less; even modest increases reduce crisis rates by approximately 50% ^[40]^D5. However, a large pharmacokinetic study found that 61% of HU-prescribed patients ≥10 years and 76% of those <10 years had undetectable drug levels, correlating with lower MCV and HbF ^[292]^C4 (4). This highlights adherence as a critical barrier; routine monitoring of HU blood levels or MCV can identify suboptimal dosing before clinical failure.

Step 2: Add or Switch to Novel Oral Agents When Response Is Inadequate

Three additional orally administered therapies have shown efficacy in phase 3 trials and are approved (in the US) for sickle cell disease.

L-glutamine (Endari) - Oral therapy (0.3 g/kg/dose twice daily) that reduces oxidative stress. In the phase 3 trial (N=230), the L-glutamine group had a median of 3.0 pain crises over 48 weeks vs 4.0 in the placebo group (P=0.005); hospitalizations also decreased (median 2.0 vs 3.0, P=0.005) ^[17]^A1b (1b). NNT to prevent one crisis was not calculable from reported data, but the absolute difference was 1 crisis per 48 weeks. Two-thirds of patients were on concomitant hydroxyurea, supporting additive benefit.

Voxelotor (Oxbryta) - An HbS polymerization inhibitor dosed at 1500 mg orally once daily. In the HOPE trial (N=274), 51% of voxelotor-treated patients achieved a hemoglobin increase >1 g/dL at 24 weeks vs 7% on placebo (P<0.001) ^[19]^A1b (1b). NNT = 2.3 for a hemoglobin response. Hemolysis markers (indirect bilirubin, reticulocytes) also declined. Voxelotor is particularly suited for patients with baseline Hb <9 g/dL and frequent VOC.

Mitapivat (Pyrukynd) - An oral pyruvate kinase activator that increases RBC ATP and reduces 2,3-DPG. In the RISE UP phase 2 portion (N=79), hemoglobin response rates were 46% (50 mg BID) and 50% (100 mg BID) vs 4% placebo (P=0.0003 and P=0.0001, respectively) ^[149]^A1b (1b). NNT ≈ 2.2 for both doses. One-year follow-up data showed sustained Hb improvement (mean increase 1.1 ± 0.7 g/dL) and a reduction in annualized vaso-occlusive events from 1.33 at baseline to 0.64 ^[249]^B2b (2b). Mitapivat is well tolerated; serious adverse events occurred in 8-15% of treated patients over the phase 2 period.

Crizanlizumab (Adakveo) - A P-selectin monoclonal antibody (5 mg/kg IV every 4 weeks after a loading dose). The SUSTAIN phase 2 trial showed a 45.3% lower rate of pain crises vs placebo (median 1.63 vs 2.98 per year, P=0.01) ^[18]^A1b (1b). However, the subsequent phase 3 STAND trial (N=252) found no significant difference in annualized VOC rates between crizanlizumab 5.0 mg/kg (2.49), 7.5 mg/kg (2.04), and placebo (2.30); the rate ratios vs placebo were 1.08 and 0.89 ^[70]^A1b (1b). Grade ≥3 adverse events were more frequent in the 5.0 mg/kg group (56%) vs placebo (32%). Given these conflicting results, crizanlizumab is not recommended as first- or second-line therapy; it may be considered only in the context of shared decision-making and after discussing the STAND data.

Other emerging agents - Etavopivat, another PK activator, produced a mean maximal Hb increase of 1.6 g/dL over 12 weeks in a phase 1 study ^[242]^A1b (1b). Riociguat (a soluble guanylate cyclase stimulator) did not increase serious adverse events compared to placebo and modestly lowered blood pressure, but it is not yet approved for SCD ^[115]^A1b (1b).

Drug / Modality Comparison Table

Agent	Indication / Line	Dose	Key Trial	Hemoglobin Response	Crisis Reduction	Evidence Level
Hydroxyurea	First-line	15-20 mg/kg/day → MTD	BABY HUG, MSH	HbF ↑; Hb ↑ 0.5-1 g/dL	~50% reduction	1b ^[40]^D5
L-glutamine	Second-line (add-on)	0.3 g/kg/dose BID	Phase 3 ^[17]^A1b	No significant Hb increase	Median 1 fewer crisis/48 weeks	1b
Voxelotor	Second-line (anemia predominant)	1500 mg once daily	HOPE ^[19]^A1b	51% with Hb ↑ >1 g/dL; NNT=2.3	Not significant for VOC	1b
Mitapivat	Second-line (hemolysis + VOC)	50-100 mg BID	RISE UP ^[149]^A1b	46-50% with Hb ↑ >1 g/dL; NNT=2.2	Annualized VOC ↓ from 1.33 to 0.64	1b
Crizanlizumab	Third-line (controversial)	5 mg/kg IV q4wk	SUSTAIN ^[18]^A1b vs STAND ^[70]^A1b	None	SUSTAIN: 45% reduction; STAND: none	1b (mixed)

Step 3: Refer for Curative Therapy - Hematopoietic Stem Cell Transplantation or Gene Therapy

For patients with severe disease (recurrent VOC despite optimized medical therapy, stroke, or progressive organ damage), curative approaches should be discussed. Allogeneic HSCT from a matched sibling donor offers 2-year event-free survival of 82-95% and overall survival ~ ^[152]^C4 (4) ^[240]^A1c (1c). The ASH 2021 guidelines recommend considering HSCT for children with neurologic injury or recurrent acute chest syndrome (conditional recommendation, very low certainty) ^[240]^A1c. Nonmyeloablative haploidentical regimens using post-transplant now achieve durable engraftment in adults with a 5-year OS of 95.5% ^[76]^C4 (4). Gene therapies - including exagamglogene autotemcel (exa-cel, CRISPR-Cas9 editing of BCL11A) and lovotibeglogene autotemcel (lovo-cel, lentiviral β-globin addition) - eliminate severe VOC in 97-100% of treated patients after myeloablative busulfan conditioning ^[243]^B2b (2b) ^[244]^B2b (2b). The detailed evidence for these modalities is presented in Section 9 (Hematopoietic Cell Transplantation & Cellular Therapy).

Controversies and Guideline Disagreement

Question	Position A	Position B	Strength of disagreement	Implication for practice
Should crizanlizumab be used after STAND?	ASH 2020 pain guidelines predate STAND and do not address; some clinicians still cite SUSTAIN	STAND authors and many experts conclude no evidence of efficacy ^[70]^A1b	Strong (SUSTAIN positive vs STAND negative) ^[18]^A1b^[70]^A1b	Crizanlizumab should not be routinely prescribed. If used, discuss conflicting trial results.
Optimal HU dosing strategy	NCCN/ASH recommend escalating to MTD with neutropenia target	Some centers use fixed moderate doses (15-20 mg/kg) to avoid toxicity	Mild (wording differences; both acknowledge need for individualization) ^[40]^D5	Monitor MCV, HbF, and consider HU blood levels to confirm adherence, especially in young children ^[292]^C4.

What NOT to Do

Do not prescribe crizanlizumab as first- or second-line therapy - the STAND phase 3 trial failed to confirm SUSTAIN’s efficacy; the drug is associated with high-grade adverse events and costs ^[70]^A1b.

Pearl: Begin hydroxyurea early and titrate to MTD; if VOC or anemia persist, add voxelotor (for anemia) or mitapivat (for hemolysis/VOC) - both have NNT ≈2 for a hemoglobin response - and refer for curative HSCT/gene therapy in eligible patients with severe disease ^[149]^A1b^[19]^A1b^[17]^A1b.

Key Points:

Hydroxyurea remains first-line; adherence monitoring with drug levels or MCV is essential to avoid suboptimal response.
Voxelotor and mitapivat each more than double the chance of a clinically meaningful hemoglobin increase compared to placebo (NNT ~2).
Crizanlizumab’s benefit is unconfirmed after the negative STAND trial; it should not be routinely used.
Curative therapies (HSCT, gene therapy) should be discussed early for patients with severe complications.

9. Hematopoietic Cell Transplantation & Cellular Therapy

▸HLA-identical sibling HSCT with myeloablative conditioning achieves 5-year event-free survival >90% in children, with best results when performed before age 10 years.
▸Nonmyeloablative allogeneic approaches (haploidentical with PTCy) and autologous gene therapy (exa-cel, lovo-cel) offer cure for patients without matched sibling donors, but carry risks of graft failure, GVHD, or busulfan-related toxicity.
▸Gene therapy eliminates vaso-occlusive crises in >95% of patients with severe SCD, but long-term safety data (secondary neoplasms, fertility) remain incomplete; lifelong surveillance is mandatory.

! Warning: Filgrastim (G-CSF) is contraindicated for stem cell mobilization in SCD due to risk of severe vaso-occlusive complications. Use plerixafor after red cell exchange to lower HbS <30% [159, 312].

! Warning: Sickle cell disease is an independent risk factor for transplant-associated thrombotic microangiopathy (TA-TMA). Monitor closely for hypertension, thrombocytopenia, and elevated lactate dehydrogenase after HSCT, particularly after haploidentical transplantation (OR 33 vs matched sibling) [94].

Building on disease-modifying therapies, curative-intent allogeneic hematopoietic stem cell transplantation (HSCT) and autologous gene therapy have become standard options for patients with severe sickle cell disease (SCD). The choice between these approaches hinges on donor availability, organ function, age, and patient preference.

Allogeneic Hematopoietic Stem Cell Transplantation

Allogeneic HSCT from an HLA-matched sibling donor is the most established curative therapy, with 5-year overall survival (OS) exceeding 90% in children. In a multicenter international survey of 1000 recipients (median age 9 years, 87% myeloablative conditioning), 5-year OS was 92.9% and event-free survival (EFS) was 91.4% (89.6-93.3) ^[302]^B2b. Outcomes are better when transplantation occurs before age 10 years (hazard ratio for EFS 1.09 per year; p<0.001) and after 2006 ^[302]^B2b^[314]^B2b. Among 44 patients transplanted after January 2000 in France, EFS reached 95.3% ^[305]^C4.

Donor source and conditioning regimen. A retrospective analysis of 910 US transplants (2008-2017) found that EFS was significantly worse with haploidentical, matched unrelated (, 2.39-5.75), and mismatched unrelated donors (HR 4.34, 2.58-7.32) compared with matched siblings ^[156]^B3b. Age ≥13 years also predicted worse EFS (, 1.24-2.45;) ^[156]^B3b. The ASH 2021 guideline (based on very low certainty evidence) recommends considering HSCT for patients with neurologic injury or recurrent acute chest syndrome at an early age ^[240]^A1c. The European Blood and Marrow Transplantation (EBMT) inborn error working party consensus recommends HLA-identical sibling HSCT as standard for children with severe SCD ^[241]^A1c.

Myeloablative conditioning, typically busulfan plus or fludarabine, yields OS >97% and EFS >90% in matched sibling transplants ^[302]^B2b^[305]^C4^[323]^C4. A recent EBMT pediatric study (n=251) comparing busulfan-fludarabine (bu-flu) vs treosulfan-fludarabine (treo-flu) showed 2-year OS 98.7% (90.9-99.8) and 99.3% (95.2-99.9), respectively ^[104]^B2b. Grade III-IV acute GVHD at day 100 was 2.4% (0.4-7.5) with bu-flu and 0.6% (0.1-3.2) with treo-flu; extensive chronic GVHD at 2 years 1.5% (0.1-7.3) and 8.0% (4.1-13.3) ^[104]^B2b.

Nonmyeloablative and reduced-intensity regimens are increasingly used for older patients to lower toxicity. The NIH protocol using alemtuzumab, 300 cGy total body irradiation (TBI), and in adults (n=10) achieved stable mixed donor chimerism with OS 100% at median 30 months; no acute or chronic GVHD occurred ^[248]^C4. A multi-center pediatric replication (n=38) with the same regimen reported 2-year OS 100% and EFS 78.9%; secondary graft failure occurred in 18.4% ^[295]^C4. For matched related donors, a nonmyeloablative haploidentical platform with post-transplant cyclophosphamide (PTCy) is highly promising. In an international phase 2 trial (n=70), 2-year EFS was 82.6% and OS 94.1%; graft failure occurred in 11.4% (all children <18 years) ^[152]^C4. A single-center series using 400 cGy TBI with PTCy (n=43) reported 5-year OS 95.5% (87-100) and 2-year disease-free survival 94.5% (87-100), with a 5% graft failure rate ^[76]^C4.

Graft-versus-host disease and complications. In HLA-matched sibling transplants, acute GVHD rates range from 5-15% and chronic GVHD from 8-22%; GVHD is the leading cause of transplant-related mortality ^[302]^B2b^[305]^C4^[323]^C4. Unrelated donor transplants carry higher GVHD rates: one BMT CTN trial reported day-100 acute GVHD (grade II-IV) 28%, 1-year chronic GVHD 62% (38% extensive), and 7 GVHD-related deaths among 29 patients ^[74]^B2b. SCD itself is an independent risk factor for transplant-associated thrombotic microangiopathy (TA-TMA) (OR 12.22, 95%) ^[94]^B2b. Secondary neoplasms occur at a 10-year incidence of 2.4% (1.4-3.8) after transplant; notably, low-intensity regimens containing TBI were associated with a higher risk of leukemia/MDS (HR 22.69, 4.34-118.66) compared with myeloablative regimens ^[90]^B2b.

Autologous Gene Therapy and Gene Editing

Gene therapy approaches use autologous CD34+ hematopoietic stem cells modified ex vivo to increase fetal hemoglobin or correct the sickle mutation, then reinfused after myeloablative conditioning with busulfan. The ASH 2021 guideline notes no randomized trials, but single-arm studies show high rates of freedom from vaso-occlusive crises ^[240]^A1c. The ASTCT/ISCT 2026 consensus provides practice recommendations including eligibility assessment, mobilization (plerixafor preferred over filgrastim), fertility preservation, and lifelong surveillance ^[306]^A1c.

Exagamglogene autotemcel (exa-cel) is a CRISPR-Cas9-edited therapy targeting the BCL11A enhancer. In the phase 3 CLIMB SCD-121 trial (n=44, median follow-up 19.3 months), 29 of 30 evaluable patients (97%; 95% CI 83-100) were free from severe vaso-occlusive crises for ≥12 months, and all 30 (100%; 88-100) were free from hospitalization, both significantly exceeding the prespecified 50% null hypothesis (p<0.001) ^[243]^B2b. No cancers occurred ^[243]^B2b. In children aged 5-11 years, 8 of 8 evaluable patients (100%) achieved freedom from vaso-occlusive crises at ≥16 months ^[262]^C4.

Lentiviral gene addition (lovotibeglogene autotemcel, lovo-cel) achieved resolution of severe VOEs in 100% (25/25) of evaluable patients in the pivotal HGB-206 cohort [as summarized in 286]. Early results from the RUBY trial of renizgamglogene autogedtemcel (reni-cel; CRISPR-Cas12a editing of HBG1/HBG2 promoters) showed a mean hemoglobin increase from 9.8 to 13.8 g/dL at 6 months and fetal hemoglobin rise to 48.1±3.2%; only 1 of 28 patients had post-infusion severe VOEs (median follow-up 9.5 months) ^[247]^B2b. The BEACON trial of ristoglogene autogetemcel (risto-cel; base editing) reported a 67.4% mean on-target editing, HbF >60% of total hemoglobin at 6 months, and no investigator-reported severe VOEs beyond day 60 (31 patients, mean follow-up 6.6 months) ^[246]^B2b.

Mobilization and manufacturing. Plerixafor (0.24 mg/kg subcutaneously) safely mobilizes CD34+ cells in SCD patients after red cell exchange to lower HbS <30%; it yields high stem-cell yields with no adverse events reported ^[159]^C4. Filgrastim is avoided due to risk of severe vaso-occlusive complications ^[159]^C4^[312]^D5.

Toxicity. All gene therapy platforms require myeloablative busulfan conditioning, which is associated with mucositis, veno-occlusive liver disease, infertility, and a small risk of secondary myelodysplasia/leukemia (observed in early lentiviral trials; busulfan and possibly clonal selection are implicated) ^[304]^D5^[306]^A1c. One death from idiopathic pneumonia syndrome occurred after risto-cel ^[246]^B2b.

Controversies and Guideline Disagreement

Question	Position A	Position B	Strength	Implication for practice
Allogeneic HSCT vs gene therapy as preferred curative option	ASH 2021 guideline notes HSCT is the only currently proven cure, but recommends shared decision-making and registry enrolment for gene therapy ^[240]^A1c	ASTCT/ISCT 2026 recommends gene therapy as a viable alternative when HLA-identical sibling donor is unavailable, acknowledging comparable short-term efficacy ^[306]^A1c	Moderate (divergent emphasis on evidence maturity)	Patients lacking a matched sibling should be offered both allogeneic alternative donor transplant and gene therapy; the choice depends on organ function, availability of haploidentical donor, fertility concerns, and access to specialized cell therapy centres ^[318]^D5^[326]^D5
Conditioning regimen intensity for matched sibling HSCT	EBMT 2014 consensus recommends myeloablative conditioning (busulfan- or treosulfan-based) as standard for children ^[241]^A1c	Recent nonmyeloablative regimens (e.g., NIH alemtuzumab/300cGy) show excellent OS with lower acute toxicity but higher graft failure (18.4%) ^[295]^C4	Strong (differing risk/benefit trade-off)	For children, myeloablative conditioning remains the benchmark; nonmyeloablative approaches may be suitable for adults with significant organ damage, though graft failure risk must be weighed ^[314]^B2b^[316]^D5

Pearl: For a child with severe SCD and an HLA-identical sibling, myeloablative HSCT offers >95% event-free survival; for patients without a matched sibling, both haploidentical HSCT (with PTCy) and autologous gene therapy (exa-cel, lovo-cel) provide >80% freedom from vaso-occlusive crises, but each carries distinct risks of GVHD, graft failure, or busulfan toxicity that must be individualized.

Overview of Curative Therapies for Sickle Cell Disease

Therapy	Donor source	Conditioning	Key efficacy	Key safety concerns	Evidence level
HLA-identical sibling HSCT	Matched sibling	Myeloablative (bu-cy, bu-flu, treo-flu)	5-year OS 93-98%, EFS 91-95% ^[302]^B2b^[104]^B2b	Acute GVHD 10-15%, chronic GVHD 8-22%, graft failure <10% ^[302]^B2b^[323]^C4	1b-2b ^[302]^B2b^[104]^B2b
Matched unrelated donor HSCT	8/8 HLA-matched unrelated	Myeloablative or reduced-intensity	2-year EFS 69% ^[74]^B2b; OS 79% ^[74]^B2b	Acute GVHD 28%, chronic GVHD 62% (38% extensive) ^[74]^B2b; high TRM	2b ^[74]^B2b
Haploidentical HSCT with PTCy	Haploidentical related donor	Nonmyeloablative (TBI 200-400 cGy, Flu, Cy, ATG)	2-year EFS 83%, OS 94% ^[152]^C4; 5-year OS 95.5% ^[76]^C4	Graft failure 5-11%; acute GVHD 2-10%, chronic GVHD 7-10%; TA-TMA risk increased ^[94]^B2b^[76]^C4	4 ^[152]^C4^[76]^C4
Exagamglogene autotemcel (exa-cel)	Autologous (CRISPR-Cas9-edited)	Myeloablative busulfan	97% freedom from severe VOEs at ≥12 months ^[243]^B2b	Veno-occlusive liver disease, infertility, secondary MDS/leukemia (rare) ^[304]^D5	2b ^[243]^B2b
Lovo-cel (lentiviral gene addition)	Autologous (lentiviral β-globin)	Myeloablative busulfan	100% resolution of severe VOEs (evaluable patients) ^[286]^C4	Busulfan toxicity, insertional mutagenesis risk ^[304]^D5^[300]^D5	2b ^[286]^C4
Reni-cel (CRISPR-Cas12a)	Autologous (HBG1/HBG2 editing)	Myeloablative busulfan	Mean Hb 13.8 g/dL, HbF 48% at 6 months; only 1/28 with post-infusion VOE ^[247]^B2b	Busulfan toxicity; early follow-up (median 9.5 months) ^[247]^B2b	2b ^[247]^B2b
Risto-cel (base editing)	Autologous (HBG1/HBG2 base editing)	Myeloablative busulfan	HbF >60%, no investigator-reported severe VOEs after day 60 ^[246]^B2b	One death from idiopathic pneumonia syndrome; busulfan toxicity ^[246]^B2b	2b ^[246]^B2b

Abbreviations: bu-cy, busulfan + cyclophosphamide; bu-flu, busulfan + fludarabine; treo-flu, treosulfan + fludarabine; ATG, antithymocyte globulin; Flu, fludarabine; Cy, cyclophosphamide; PTCy, post-transplant cyclophosphamide; TBI, total body irradiation; GVHD, graft-versus-host disease; TA-TMA, transplant-associated thrombotic microangiopathy; MDS, myelodysplastic syndrome; VOE, vaso-occlusive event; HbF, fetal hemoglobin.

10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)

▸Transfusion with ABO/Rh/Kell matching reduces alloimmunization; avoid transfusion during proinflammatory events whenever possible.
▸Hydroxyurea is first-line disease-modifying therapy but adherence is poor; voxelotor and crizanlizumab are evidence-based alternatives.
▸Anticoagulation for VTE follows standard guidelines; antiplatelet agents have no role for VOC prevention.

! Warning: Avoid additional RBC transfusion during delayed hemolytic transfusion reaction (DHTR) unless life-threatening; further transfusion can worsen hemolysis and prolong hospitalization [79, 140].

For patients who cannot access or decline curative cellular therapy, the hematology triad, transfusion support, anticoagulation, and disease-modifying therapy, remains the backbone of morbidity and mortality reduction.

Transfusion Support

Transfusion is indicated acutely for , , , and aplastic crisis, and chronically for primary and secondary prevention and prior to medium- or high-risk surgery ^[239]^A1c^[331]^A1b. The TAPS trial demonstrated that preoperative transfusion reduced perioperative complications from 39% to 15% (OR 3.8, 95%) ^[331]^A1b.

Method selection: Simple transfusion suffices for acute anemia; erythrocytapheresis (automated exchange) is preferred when the target fraction is <30%, as in stroke prophylaxis, because it limits iron loading and hyperviscosity ^[239]^A1c^[333]^D5.

Antigen matching: The ASH 2020 guideline and the International Collaboration for Transfusion Medicine Guidelines recommend selecting RBCs compatible for ABO, Rh (D, C, c, E, e), and Kell for all patients with SCD, even without prior antibodies ^[239]^A1c^[330]^B2a (conditional recommendation). Extended matching reduces alloimmunization prevalence from ~29% to below 10% ^[290]^B2a^[330]^B2a. Transfusion during a proinflammatory event increases alloimmunization risk 4-fold (OR 4.22, 95%) ^[337]^B3b.

Delayed hemolytic transfusion reaction (DHTR): Suspect DHTR when hemoglobin falls 5-14 days post-transfusion with pain, fever, and hemoglobinuria. Do not transfuse again unless absolutely necessary, additional RBCs may prolong recovery ^[79]^C4. First-line therapy includes intravenous immune globulin (IVIG) and corticosteroids; erythropoietin is added if reticulocytopenia is present ^[140]^C4^[79]^C4.

Iron overload: Start chelation when serum ferritin >1000 ng/mL or liver iron >5 mg/g dry weight by MRI ^[343]^D5. Options include deferasirox (20-40 mg/kg/day), deferiprone (75-100 mg/kg/day), and deferoxamine ^[327]^A1b^[343]^D5.

Anticoagulation

SCD creates a hypercoagulable state: elevated , decreased ADAMTS13 activity, platelet activation, and phosphatidylserine-exposed RBCs ^[58]^D5^[46]^D5^[60]^B2b. The ASH 2019 guideline recommends VTE prophylaxis for hospitalized adults with SCD (conditional recommendation, very low certainty) ^[151]^A1c. For acute VTE, treat with standard anticoagulation (low-molecular-weight or DOACs); indefinite anticoagulation is considered after unprovoked or recurrent VTE ^[151]^A1c^[344]^D5. Antiplatelet agents, including , have not reduced VOC rates (rate ratio 1.06, 95%) ^[69]^A1b.

Disease-Modifying Therapy

Drug	Starting dose	Target / max dose	Key monitoring	Key trial / evidence
	15-20 mg/kg/day PO	MTD (ANC 2000-4000/μL)	CBC every 4 wk, HbF every 3-6 mo	Multicenter RCTs show reduced VOC, ACS, transfusion ^[40]^D5
	1500 mg PO once daily	1500 mg daily (no titration)	Hb, markers	HOPE trial: Hb response 51% vs 7% (p<0.001) ^[71]^A1b
*	5 mg/kg IV over 30 min	5 mg/kg IV wk 0, wk 2, then q4wk	VOC rate	SUSTAIN trial: median VOC rate 1.63 vs 2.98 per year ^[38]^D5^[340]^D5

*Dosing per FDA label but not detailed in provided abstracts; listed for completeness.

Hydroxyurea remains first-line for most patients with frequent VOC or moderate-to-severe disease. Adherence is a major barrier: in the GenoMed4All cohort, HU was undetectable in 61% of prescribed patients ≥10 years and 76% of those <10 years, despite comparable dosing ^[292]^C4. Voxelotor targets HbS polymerization and raises hemoglobin by ~1 g/dL ^[71]^A1b.

Controversies and Guideline Disagreement

Question	Position A	Position B	Strength	Implication
Method of transfusion for primary stroke prevention	ASH 2020 recommends chronic simple transfusion or exchange to maintain HbS <30% ^[239]^A1c	NICE does not specify method; both accepted	Mild (wording)	Either method is acceptable; exchange reduces iron loading but requires apheresis access
Duration of anticoagulation for first provoked VTE	ASH 2019 suggests 3-6 months ^[151]^A1c	No contradictory guideline identified	None	Standard duration applies

Pearl: For all SCD patients receiving RBC transfusions, use ABO/Rh/Kell-matched units and avoid transfusion during proinflammatory events when possible, the risk of alloimmunization rises 4-fold with inflammatory triggers ^[337]^B3b, and extended matching reduces it substantially ^[239]^A1c^[330]^B2a.

History and Evolution of Treatment

▸Hydroxyurea, approved in 1998, remains the standard-bearer for chronic disease modification, with decades of safety and efficacy data behind it.
▸Three drugs approved between 2017-2019 (L-glutamine, crizanlizumab, voxelotor) provided alternative mechanisms but subsequent trials (STAND for crizanlizumab) failed to replicate initial results, highlighting the need for confirmatory phase 3 data.
▸Curative gene therapy (exa-cel, lovo-cel) now offers >95% freedom from severe vaso-occlusive events in pivotal cohorts, though long-term safety and equitable access remain unresolved.

HY High Yield: The STAND trial [70] and the MSH trial [51] illustrate a recurring pattern: early promising phase 2 data may not survive phase 3. Always seek confirmatory data before adopting new therapies.

Building on the transfusion and cytoreductive strategies just reviewed, the therapeutic timeline for sickle cell disease has progressed from supportive care through disease-modifying pharmacotherapy to curative cellular and gene therapies. Each era was defined by landmark trials that either established a new standard or closed the door on a promising candidate.

The Hydroxyurea Era

Hydroxyurea (hydroxycarbamide) became the first FDA-approved disease-modifying therapy for sickle cell anemia in 1998, based on the Multicenter Study of Hydroxyurea in Sickle Cell Anemia (MSH) showing reduced pain crises and acute chest syndrome ^[51]^D5. By inducing fetal hemoglobin (HbF), it inhibits HbS polymerization. Long-term pediatric data confirmed tolerability and clinical benefit over a median 3.8 years, though treatment failure and non-compliance led to discontinuation in some ^[369]^C4. Hydroxyurea remains the backbone of chronic therapy, yet adherence gaps persist ^[379]^C4.

Targeted Therapies: 2017-2019

After decades with only hydroxyurea, three new drugs gained FDA approval between 2017 and 2019. L-glutamine (0.3 g/kg twice daily) reduced median pain crises from 4.0 to 3.0 over 48 weeks (P=0.005) and hospitalizations from 3.0 to 2.0 (P=0.005) in a phase 3 trial that included patients on concomitant hydroxyurea ^[17]^A1b. Low-grade nausea and fatigue were more frequent in the glutamine group. Crizanlizumab, a P-selectin inhibitor (5 mg/kg IV), lowered the annual rate of pain crises by 45.3% versus placebo (1.63 vs 2.98, P=0.01) in the SUSTAIN trial ^[18]^A1b. Voxelotor (1500 mg once daily), an HbS polymerization inhibitor, achieved a hemoglobin response (>1 g/dL increase) in 51% of patients versus 7% with placebo (P<0.001), with concomitant reductions in markers ^[19]^A1b.

Disappointments and Lessons

Several high-profile trials failed to confirm efficacy. The phase 3 HESTIA3 trial found no better than placebo for preventing vaso-occlusive crises in children (rate ratio 1.06) ^[69]^A1b. Ketoprofen 300 mg/day for 5 days showed no benefit over placebo for VOC duration or consumption ^[353]^A1b. The anti-adhesive agent sevuparin did not shorten time to VOC resolution ^[150]^A1b. Riociguat, a soluble guanylate cyclase stimulator, was safe but did not reduce vaso-occlusive events or pain severity (difference -5.2%) ^[115]^A1b. Most tellingly, the phase 3 STAND trial failed to replicate crizanlizumab's earlier promise: adjusted annualized VOC rates were 2.04 (7.5 mg) versus 2.30 with placebo (rate ratio 0.89) ^[70]^A1b. These results underscore the challenges of trial design in SCD and the importance of confirmatory studies ^[389]^D5.

Emerging Small Molecules

Mitapivat, an oral pyruvate kinase activator, produced a hemoglobin response in 46% (50 mg BID) and 50% (100 mg BID) of patients versus 4% for placebo (P=0.0003 and P=0.0001) in the phase 2 RISE UP study, with improvements in hemolysis markers ^[149]^A1b. Etavopivat (400 mg once daily) increased hemoglobin by a mean of 1.6 g/dL, with 73% of patients achieving a ≥1 g/dL rise over 12 weeks ^[242]^A1b. Both agents are advancing to phase 3 trials.

From Transplant to Gene Therapy

Allogeneic hematopoietic stem cell transplantation from an HLA-identical sibling has been curative since the 1990s: a seminal series reported 91% survival and 73% event-free survival at 4 years ^[362]^C4. The ASH 2021 guidelines recommend considering HSCT for children with neurologic injury or recurrent acute chest syndrome at an early age ^[240]^A1c. Nonmyeloablative regimens have reduced toxicity but graft failure remains a concern; increasing total body irradiation from 200 to 400 cGy lowered primary graft failure to 6% in one haploidentical protocol ^[153]^C4.

Gene therapy entered clinical practice with FDA approvals in 2023. Lovo-cel (LentiGlobin) achieved sustained HbAT87Q production (≥40% of total hemoglobin), normalized hemolysis markers, and resolved severe vaso-occlusive events in all 25 evaluable patients (median follow-up 17.3 months) ^[244]^B2b. Exagamglogene autotemcel (exa-cel, CRISPR-Cas9-edited) showed 96.7% freedom from severe VOC at 12 months in the pivotal cohort ^[286]^C4. Practical recommendations from ASTCT and ISCT emphasize careful patient selection, fertility preservation, myeloablative conditioning with busulfan, and lifelong surveillance for late effects ^[306]^A1c.

The Road Ahead

Over 30 investigational agents are in clinical development, many targeting complementary pathways, adhesion, inflammation, nitric oxide bioavailability, and HbF reactivation, raising the prospect of rational combination therapy ^[51]^D5. Endurance exercise training has also shown benefit in improving muscle microvasculature and reducing VOC risk ^[355]^A1b. As the therapeutic arsenal expands, the challenge shifts from developing new drugs to delivering them equitably and integrating them into a coordinated, lifelong care plan ^[264]^D5.

Pearl: The history of SCD therapy teaches that phase 2 promise often does not survive phase 3 scrutiny, confirmatory trials are essential before adopting new agents, and hydroxyurea remains the only disease-modifying therapy with decades of safety and efficacy data.

Landmark trials that shaped SCD therapy

Therapy	Pivotal trial	Key efficacy result	Current status
Hydroxyurea	MSH (1995)	Reduced pain crises and ACS	Standard of care
L-glutamine	NEJM 2018 ^[17]^A1b	Median crises 3.0 vs 4.0 (P=0.005)	FDA-approved, used as add-on
Crizanlizumab	SUSTAIN (2016) ^[18]^A1b	45.3% lower crisis rate (P=0.01)	FDA-approved; STAND trial ^[70]^A1b failed to replicate
Voxelotor	HOPE (2019) ^[19]^A1b	Hemoglobin response 51% vs 7% (P<0.001)	FDA-approved
Mitapivat	RISE UP phase 2 (2024) ^[149]^A1b	Hb response 46-50% vs 4% (P≤0.0003)	Ongoing phase 3
Exa-cel gene therapy	Pivotal cohort ^[286]^C4	96.7% free of severe VOC at 12 months	FDA-approved
Lovo-cel gene therapy	HGB-206 (2021) ^[244]^B2b	100% resolution of severe VOC	FDA-approved

11. Complications

▸VTE incidence is 5.2/1000 person-years and carries a 2.3-fold increased mortality risk, warranting routine pharmacologic prophylaxis during hospitalization [111].
▸Invasive pneumococcal disease persists despite conjugate vaccines; serogroup 15 accounts for >50% of breakthrough cases, reinforcing the need for continued penicillin prophylaxis [120].
▸Acute chest syndrome remains the leading cause of ICU admission; early use of incentive spirometry during VOC reduces its incidence [127].

HY High Yield: The three pillars of complication prevention in sickle cell disease are infection prophylaxis (penicillin + vaccines), stroke screening (TCD from age 2 years), and disease-modifying therapy (hydroxyurea) [41,400].

Treatment advances have extended survival, but sickle cell disease still produces a broad spectrum of acute and chronic complications driven by vaso-occlusion, , and chronic inflammation ^[41]^D5^[85]^D5^[137]^D5. The table below catalogues the most frequent events, linked to their mechanisms and principles.

Complication	Frequency	Prevention	Management
Acute vaso-occlusive crisis (VOC)	1-2 episodes per patient-year ^[144]^B2a	Hydroxyurea, hydration, avoidance of triggers	Parenteral opioids, IV fluids, incentive spirometry ^[127]^D5
Acute chest syndrome (ACS)	Incidence 12.8 per 100 patient-years ^[41]^D5	Incentive spirometry during VOC, hydroxyurea	(macrolide), simple/partial exchange transfusion, respiratory support ^[127]^D5
Stroke	11% of children by age 20 without screening ^[394]^B3b	Transcranial Doppler screening, chronic transfusion for abnormal velocities	Acute: exchange transfusion; chronic: transfusion or hydroxyurea ^[41]^D5
Splenic sequestration	<10% of children with HbSS ^[395]^B2a	Parent education, early recognition	Emergency transfusion, splenectomy if recurrent ^[401]^D5
Infection/sepsis	Invasive pneumococcal disease prevalence 1.9% in PCV era ^[120]^B2a	Penicillin prophylaxis, conjugate vaccines (PCV13, Hib, meningococcal) ^[275]^D5^[400]^D5	Broad-spectrum antibiotics, ICU support
Venous thromboembolism (VTE)	5.2 events/1000 person-years; PE > DVT ^[111]^B2b	VTE prophylaxis during hospitalization ( 40 mg SC daily)	Anticoagulation per standard guidelines; higher mortality in SCD (HR 2.32) ^[111]^B2b
Renal disease (sickle cell nephropathy)	Proteinuria in 20-30% of adults ^[21]^B2a	ACE inhibitors for albuminuria, hydroxyurea ^[41]^D5	ACEi/ARB, dialysis, renal transplantation ^[307]^D5
	30-45% of males ^[22]^D5	PDE5 inhibitors for stuttering attacks, education ^[22]^D5	Aspiration ± irrigation, α-adrenergic agonists; detumescence <4 h is key ^[22]^D5
Leg ulcers	10-20% of adults ^[175]^D5	Compression, wound care, hydroxyurea	Debridement, skin grafts, transfusion ^[175]^D5

Respiratory Monitoring

During ACS or severe VOC, monitor and respiratory rate. Intubation criteria include SpO₂ < 90% despite 60% FiO₂, PaCO₂ > 50 mm Hg, declining mental status, or impending respiratory failure ^[127]^D5. FVC < 50% of predicted may signal need for noninvasive ventilation or escalation ^[127]^D5.

Autonomic and Other Complications

Autonomic dysfunction, arrhythmias, blood pressure lability, ileus, and urinary retention, can arise from sickling-induced microinfarction or opioid side effects. Ileus is managed with bowel rest and nasogastric decompression; catheterization is reserved for retention.

Pain Management

Acute VOC pain requires prompt : 0.1 mg/kg IV every 2-4 hours or patient-controlled analgesia. Ketorolac may be added short-term ^[150]^A1b. Chronic pain often involves neuropathic components; multidisciplinary pain programs are recommended ^[85]^D5.

Rehabilitation

Early mobilization after acute crisis reduces deconditioning. Pulmonary rehabilitation benefits those with chronic lung disease ^[355]^A1b. Physical therapy for avascular necrosis of the hip may delay arthroplasty.

Hospital-Acquired Complication Prevention

Pneumonia: incentive spirometry (10 breaths hourly) reduces ACS incidence ^[127]^D5.
Pressure injuries: turn every 2 hours, use pressure-relieving surfaces.
UTI: avoid indwelling catheters unless essential.

Pearl: Prevention strategies, penicillin prophylaxis, vaccination, hydroxyurea, and extended antigen-matched transfusion, dramatically reduce the burden of the three most common life-threatening complications: sepsis, stroke, and alloimmunization ^[41]^D5^[120]^B2a^[290]^B2a^[400]^D5.

12. Prognosis & Natural History

▸Life expectancy in high-income settings averages 52.6 years, but under‑5 mortality in sub‑Saharan Africa remains 15-90% without intervention.
▸Tricuspid regurgitant jet velocity ≥2.5 m/s (HR 3.03) and elevated NT‑proBNP (HR 1.68 per log) are the strongest independent predictors of adult death.
▸Venous thromboembolism doubles mortality risk (HR 2.32); cumulative VTE incidence reaches 11.3% by age 40.

HY High Yield: Annual echocardiographic screening for TR jet velocity ≥2.5 m/s is the most impactful prognostic tool in adult SCD; an elevated value (HR 3.03) should prompt aggressive disease-modifying therapy and consideration of transplant [407].

The cumulative organ damage described in the preceding section translates into a substantial survival penalty that varies dramatically by geography, genotype, and treatment era. In high-income countries, life expectancy for individuals with sickle cell disease receiving standard care (excluding transplant) is 52.6 years, with disparities by insurance status, those covered by Medicare for disability or end-stage renal disease fare significantly worse than those with Medicare old-age coverage ^[405]^B3b. In stark contrast, without intervention, 50-90% of children with sickle cell anaemia in sub-Saharan Africa die before age 5 years ^[31]^D5. A multicentre case-control study estimated under‑5 mortality attributable to sickle cell anaemia at **** in five African countries, and infant mortality at **** ^[406]^B3b. Globally, the under‑20 cause-specific mortality proportion is 0.029, with wide uncertainty reflecting incomplete surveillance ^[2]^A1a; the Global Burden of Disease Study 2021 estimated 34 400 cause-specific all-age deaths, but total sickle-cell-related mortality is likely far higher ^[5]^B2c.

Risk Factors for Mortality in Adults

A meta-analysis of studies from North America and Europe identified several independent predictors of death in the hydroxyurea era ^[407]^B2a:

Variable	Hazard Ratio	95% CI
Age (per 10‑year increase)	1.28	1.10-1.50
Tricuspid regurgitant jet velocity ≥2.5 m/s	3.03	2.0-4.60
log(NT‑proBNP) (per unit)	1.68	1.48-1.90
Reticulocyte count (per 1% increase)	1.05	1.01-1.10
Fetal hemoglobin (per 1% increase)	0.97	0.94-1.00

Venous thromboembolism (VTE) carries an adjusted doubling of mortality risk (HR 2.32, 95%) ^[111]^B2b. The cumulative incidence of first VTE by age 40 is 11.3%, with the highest rate in HbSS/Sβ⁰ genotype (7.6 events/1000 person‑years) ^[111]^B2b. Pulmonary embolism may be under‑diagnosed because chest CT utilization is lower in SCD inpatients than in non‑SCD inpatients ^[82]^B3b.

Natural History and Modifying Factors

Genotype determines trajectory: HbSS and HbSβ⁰ thalassaemia carry greater morbidity and mortality than HbSC or HbSβ⁺ thalassaemia ^[103]^C4^[111]^B2b. The introduction of hydroxyurea and comprehensive care has shifted survival curves in high‑income settings ^[407]^B2a, but progressive organ damage, pulmonary , chronic kidney disease, cardiomyopathy, accelerates in the third decade and remains the dominant cause of premature death ^[42]^D5. In a large transplant cohort, 5‑year overall survival after HLA‑matched sibling donor transplantation is >90%, and in a modern reduced‑intensity haploidentical regimen with 400 cGy TBI, 5‑year OS probability reached 95.5% with low graft‑versus‑host disease ^[76]^C4^[184]^C4. Gene therapy programs report vaso‑occlusive event resolution rates of 96-100% in small pivotal cohorts, though follow‑up remains short ^[286]^C4.

Neurological complications portend a particularly poor prognosis: in a Nigerian paediatric cohort, neurological manifestations were present in half of all deaths and one‑third of survivors had residual deficits ^[393]^C4.

Pearl: The single most powerful and actionable predictor of adult mortality is a tricuspid regurgitant jet velocity ≥2.5 m/s (HR 3.03); annual echocardiographic screening enables early referral and risk‑directed therapy ^[407]^B2a.

Risk Factors for Mortality in Adults with Sickle Cell Disease (Hydroxyurea Era)

Variable	Hazard Ratio	95% CI
Age (per 10-year increase)	1.28	1.10-1.50
Tricuspid regurgitant jet velocity ≥2.5 m/s	3.03	2.0-4.60
log(NT-proBNP) (per unit)	1.68	1.48-1.90
Reticulocyte count (per 1% increase)	1.05	1.01-1.10
Fetal hemoglobin (per 1% increase)	0.97	0.94-1.00

13. Special Populations & Pregnancy

▸Pregnancy in SCD increases maternal mortality 6-fold and stillbirth 4-fold; multidisciplinary care and prophylactic aspirin are recommended.
▸Pediatric SCD requires TCD screening, chronic transfusion for stroke prevention, and hydroxyurea as first-line disease-modifying therapy.
▸Elderly patients need comorbidity-adjusted dosing and individualized transfusion targets; immunocompromised patients require enhanced infection prophylaxis.

HY High Yield: In pregnant SCD patients, a systolic BP of 120 mmHg has only 21% sensitivity for detecting new or worsening proteinuria; use a lower threshold to avoid missing preeclampsia [179].

The natural history of SCD varies substantially across the lifespan, requiring age- and context-specific adaptations of standard .

Pregnancy

Pregnancy in SCD carries markedly elevated risks: maternal mortality (RR 5.98), preeclampsia (RR 2.43), (RR 3.94), preterm delivery (RR 2.21), and small-for-gestational-age infants (RR 3.72) ^[415]^B2a. are underdiagnosed because baseline blood pressures are lower in SCD; the standard 140/90 mmHg threshold has poor sensitivity (SBP 21%, DBP 5.3% in HbSS), and a lower threshold of 120/70 mmHg may better identify those needing increased surveillance ^[179]^B2b^[386]^B2b.

Antenatal management requires a multidisciplinary team including hematology, maternal-fetal medicine, and anesthesia ^[420]^D5. Prophylactic for preeclampsia prevention is recommended between weeks 12 and 36 (dose not reaching consensus) ^[424]^D5. Hydroxyurea should be discontinued before conception and avoided throughout pregnancy due to teratogenicity concerns ^[424]^D5.

Transfusion decisions remain controversial. A meta-analysis of prophylactic transfusion showed reductions in maternal mortality (OR 0.23), vaso-occlusive crises (OR 0.26), pulmonary complications (OR 0.25), and perinatal mortality (OR 0.43) ^[403]^A1a. However, the TAPS2 feasibility trial found no statistically significant differences but trends toward fewer VOCs and preterm delivery with serial prophylactic exchange transfusion ^[75]^A1b. No consensus exists on routine prophylactic transfusion; decisions should be individualized ^[424]^D5.

Delivery and postpartum: Cesarean delivery is more frequent (aRR 1.44) ^[418]^B3b. Immediate postpartum complications occur in 37% of pregnancies, most commonly vaso-occlusive pain events; hypoxia during pregnancy (OR 4.95) and unscheduled cesarean (OR 2.67) are the strongest risk factors ^[103]^C4. Postpartum VTE prophylaxis should be considered, as non-Hispanic Black individuals have the highest eligibility rates ^[108]^B2c. is safe; hydroxyurea is excreted in breast milk and contraindicated during lactation.

Pediatrics

Cerebrovascular disease remains a priority. Transcranial Doppler screening and chronic transfusion to maintain HbS <30% reduce stroke risk ^[143]^D5. Silent cerebral infarcts occur in the deep white matter where cerebral blood flow is lowest ^[413]^B2b. Voxelotor decreases cerebral oxygen extraction and blood flow, potentially reducing hemodynamic impairment ^[414]^C4. Asthma is associated with a 3-fold increased odds of overt stroke (aOR 3.05) ^[392]^B2b.

Disease-modifying therapy: Hydroxyurea pharmacokinetics are similar in children and adults; weight-based dosing (starting 20 mg/kg/day) is standard ^[368]^A1b. showed no benefit for VOC prevention ^[69]^A1b. Moderate-intensity endurance exercise (three 45-min sessions/week for 8 weeks) improved exercise capacity without adverse events ^[355]^A1b.

Chronic pain affects ~20% of adolescents; the I-STRONG program (CBT plus neuromuscular training) demonstrated feasibility and high acceptability ^[428]^C4. Vitamin D deficiency is common and associated with increased VOCs and hospitalizations; supplementation may help but evidence is insufficient ^[429]^B2a.

Transition to adult care should follow NASCC consensus standards, including a structured transfer note and definition of successful integration ^[423]^D5.

Elderly

As survival improves, older adults with SCD accumulate chronic organ damage (renal impairment, pulmonary , cardiac dysfunction). Comorbidity management must account for drug interactions (e.g., hydroxyurea dose adjustment for creatinine clearance <60 mL/min). Transfusion thresholds should be individualized; lower hemoglobin targets may be tolerated. Data on disease-modifying therapy in this age group are limited.

Immunocompromised

SCD itself causes functional asplenia, increasing susceptibility to encapsulated organisms. Prophylactic penicillin and vaccination (pneumococcal, meningococcal, type b) are essential. In patients receiving immunosuppressive therapy (e.g., after hematopoietic cell transplantation), infection prophylaxis should be intensified and live vaccines avoided.

Pearl: In pregnant women with SCD, use a lower blood pressure threshold (120/70 mmHg) to diagnose hypertensive disorders, as standard 140/90 mmHg misses most cases and delays preeclampsia management ^[179]^B2b.

Key Management Adaptations in Special Populations

Population	Key Modification	Evidence
Pregnancy	Discontinue hydroxyurea; prophylactic aspirin weeks 12-36; consider prophylactic transfusion individually	^[424]^D5, ^[403]^A1a
Pregnancy	Lower BP threshold (120/70 mmHg) for diagnosing HDP	^[179]^B2b
Pediatrics	Hydroxyurea 20 mg/kg/day; TCD screening annually ages 2-16	^[368]^A1b, ^[143]^D5
Pediatrics	Exercise training safe; I-STRONG for chronic pain	^[355]^A1b, ^[428]^C4
Elderly	Adjust hydroxyurea for renal function; monitor for drug interactions	Expert opinion
Immunocompromised	Penicillin prophylaxis; avoid live vaccines post-transplant	Standard of care

14. Prevention, Screening & Surveillance

▸Universal newborn screening with point-of-care tests (sensitivity/specificity ~100%) enables early diagnosis and initiation of penicillin prophylaxis and pneumococcal vaccination, reducing under-5 mortality in high-burden regions [164,436].
▸Annual transcranial Doppler screening from age 2, coupled with chronic transfusion or hydroxyurea for abnormal velocities, lowers overt stroke prevalence from ~11% to <1% [165,298].
▸Systematic surveillance for albuminuria (annual), pulmonary hypertension (echocardiography every 1-3 years), and retinopathy (yearly to triennial based on risk factors) permits early intervention to slow chronic organ damage [48,151,433].

HY High Yield: Newborn screening plus penicillin prophylaxis and pneumococcal vaccination reduces invasive pneumococcal disease mortality by >80% in children with SCD [436].

Beyond pregnancy and special populations, the pillars of reducing SCD morbidity and mortality are newborn screening, infection prophylaxis, and systematic surveillance for end-organ damage. In sub-Saharan Africa, where over 75% of affected children are born, mortality among children under-5 with SCD can exceed 50% without intervention ^[31]^D5. Universal newborn screening (NBS) enables early diagnosis, parental education, and initiation of prophylactic measures.

Newborn Screening and Early Diagnosis

NBS for SCD is standard in high-income countries and increasingly implemented in low- and middle-income settings using point-of-care tests (e.g., HemoTypeSC) with sensitivity and specificity approaching 100% ^[164]^C4. The Consortium on Newborn Screening in Africa (CONSA) aims to demonstrate that early screening plus standardized care reduces under-5 mortality ^[434]^D5. In Haiti, hospital-based NBS with point-of-care testing improved follow-up rates from 0% to 56% compared with traditional methods ^[435]^C4. All newborns identified with SCD should be enrolled in comprehensive care programs including folic acid supplementation, penicillin prophylaxis, and caregiver education ^[85]^D5^[275]^D5.

Infection Prevention: Prophylaxis and Vaccination

Invasive pneumococcal disease (IPD) remains a leading cause of death. With conjugate vaccines and penicillin prophylaxis, IPD incidence in children with HbSS aged 0-4 years declined by 87% (1994-1999 to 2010-2018), and case-fatality fell from 14% to 3% ^[436]^B2c. However, the incidence rate ratio versus the general population increased from 20.2 to 29.2, underscoring continued vulnerability ^[436]^B2c. Daily oral penicillin prophylaxis is recommended from diagnosis until at least age 5 ^[275]^D5. with PCV13 is given in infancy; PPSV23 is administered starting at age 2 ^[436]^B2c. Effectiveness of PPSV23 against non-PCV13 serotypes was 92% (95% CI 40.8-99.0) within 3 years ^[436]^B2c. Routine childhood immunizations including annual influenza vaccine are also indicated ^[275]^D5.

Surveillance for End-Organ Damage

Cerebrovascular

In children with HbSS/HbSβ0, annual (TCD) screening from age 2 until at least 16 years is recommended to identify those at stroke risk ^[165]^A1c. Abnormal TCD velocities (>200 cm/s) warrant transition to chronic transfusion or hydroxyurea ^[165]^A1c^[298]^D5. A single brain MRI without sedation to detect silent cerebral infarcts is suggested at least once in early school-age children and once in adults ^[165]^A1c. In low- and middle-income countries, ASH guidance supports hydroxyurea for primary stroke prevention when transfusion is not feasible ^[165]^A1c.

Renal

Annual screening for albuminuria (urine albumin-to-creatinine ratio) and estimated glomerular filtration rate should begin in childhood ^[151]^A1c^[200]^D5. In the CADRE cohort from sub-Saharan Africa, albuminuria prevalence reached 33.7% in SS/Sβ0 patients and increased with age ^[433]^C4. Early detection allows institution of angiotensin-converting enzyme inhibitors ^[151]^A1c.

Pulmonary

Screening echocardiography to measure tricuspid regurgitant jet velocity (TRV) is recommended every 1-3 years starting in adolescence ^[151]^A1c. TRV ≥2.5 m/s is associated with increased mortality risk and warrants further evaluation.

Ophthalmic

Sickle cell retinopathy (SCR) risk factors include older age, male sex, HbSC genotype, and low HbF ^[48]^D5. Yearly dilated fundus examination is advised for high-risk patients (e.g., older HbSC males); triennial screening is reasonable for low-risk patients (young HbSS females with HbF >15%) ^[48]^D5.

Patient Education

Families should be counseled on recognizing fever, splenic sequestration (abdominal distension, pallor), acute chest syndrome (cough, chest pain, fever), and stroke symptoms (focal weakness, speech difficulty, severe headache). Education on hydration, avoidance of extreme temperatures, and adherence to prophylaxis is critical. For reproductive counseling, couples at risk can be offered prenatal diagnosis or ^[84]^D5^[180]^D5.

Organ System	Screening Modality	Frequency	Guideline Source
Cerebrovascular	TCD ultrasound	Annual from age 2 to ≥16 years	ASH 2020 ^[165]^A1c
Silent infarct	MRI brain	Once in childhood, once in adulthood	ASH 2020 ^[165]^A1c
Renal	Urine ACR, eGFR	Annual	ASH 2019 ^[151]^A1c
Pulmonary	Echocardiography with TRV	Every 1-3 years (adolescence onward)	ASH 2019 ^[151]^A1c
Ophthalmic	Dilated fundus exam	Yearly (high-risk) to triennial (low-risk)	Haematologica 2024 scoping review ^[48]^D5

Pearl: For children with SCD, the combination of newborn screening, penicillin prophylaxis, pneumococcal vaccination, and annual TCD screening reduces overt stroke risk from ~11% to <1% and IPD case-fatality from 14% to 3% ^[298]^D5^[436]^B2c.

References

[1]
Kwiatkowski JL, Granger S, Brambilla DJ et al.. “Elevated blood flow velocity in the anterior cerebral artery and stroke risk in sickle cell disease: extended analysis from the STOP trial.” British journal of haematology (2006). PMID: 16848777 ↗
L2RCTCited in: 1. Definition, Classification & Nomenclature
[2]
Pimenta K, Edwards J, Ray M et al.. “Contemporary global burden of sickle cell anaemia under-5 and under-20: A systematic review and meta-analysis.” British journal of haematology (2026). PMID: 42070793 ↗
L1SR_OBSCited in: 1. Definition, Classification & Nomenclature, 12. Prognosis & Natural History, 14. Prevention, Screening & Surveillance
[3]
Ali SB, Reid M, Fraser R et al.. “Seizures in the Jamaica cohort study of sickle cell disease.” British journal of haematology (2010). PMID: 20813003 ↗
L2COHORTCited in: 1. Definition, Classification & Nomenclature
[4]
Locatelli F, Kabbara N, Ruggeri A et al.. “Outcome of patients with hemoglobinopathies given either cord blood or bone marrow transplantation from an HLA-identical sibling.” Blood (2013). PMID: 23692854 ↗
L2OTHERCited in: 1. Definition, Classification & Nomenclature, 9. Hematopoietic Cell Transplantation & Cellular Therapy
[5]
. “Global, regional, and national prevalence and mortality burden of sickle cell disease, 2000-2021: a systematic analysis from the Global Burden of Disease Study 2021.” The Lancet. Haematology (2023). PMID: 37331373 ↗
L2OTHERCited in: 1. Definition, Classification & Nomenclature, 3. Epidemiology, Etiology & Risk Factors, 8. Long-term & Definitive Management, 12. Prognosis & Natural History, 14. Prevention, Screening & Surveillance
[6]
Aurora T, Hodges R, Wardell JR et al.. “A novel US-based grading system for disease severity in sickle cell disease: the Sickle Cell Outcome Grading System (SCOGS).” The Lancet. Haematology (2026). PMID: 42242263 ↗
L5REVIEW_NARRATIVECited in: 1. Definition, Classification & Nomenclature
[7]
Grazioli A, Plazak M, Willsey K et al.. “Outcomes and survival prediction in adults with sickle cell disease treated with extracorporeal membrane oxygenation.” Blood advances (2025). PMID: 40644625 ↗
L2OTHERCited in: 1. Definition, Classification & Nomenclature, 3. Epidemiology, Etiology & Risk Factors, 7. Acute & Emergency Management
[8]
Jenkins AM, Hendry E, Power-Hays A et al.. “Increasing ketamine administration in children's hospitals for youth with sickle cell disease.” Blood advances (2026). PMID: 41337693 ↗
L4OTHERCited in: 1. Definition, Classification & Nomenclature
[9]
Srisuwananukorn A, Raslan R, Zhang X et al.. “Clinical, laboratory, and genetic risk factors for thrombosis in sickle cell disease.” Blood advances (2020). PMID: 32384541 ↗
L2OTHERCited in: 1. Definition, Classification & Nomenclature
[10]
Kumar R, Stanek J, Creary S et al.. “Prevalence and risk factors for venous thromboembolism in children with sickle cell disease: an administrative database study.” Blood advances (2018). PMID: 29431623 ↗
L2OTHERCited in: 1. Definition, Classification & Nomenclature
[11]
Wuichet K, Corty R, Bick A et al.. “Accurate identification of sickle cell disease cases in a large genotyped cohort using electronic health record data.” Blood advances (2026). PMID: 41921205 ↗
L2OTHERCited in: 1. Definition, Classification & Nomenclature
[12]
Kaweme NM, Buttress SMN, Nguweneza A et al.. “Burden and outcomes of cardiovascular and pulmonary complications in adolescents and adults with sickle cell disease: a systematic review and meta-analysis.” Systematic reviews (2026). PMID: 41673762 ↗
L1SR_OBSCited in: 1. Definition, Classification & Nomenclature, 3. Epidemiology, Etiology & Risk Factors
[13]
Ericksen PN, Dabbous F, Ghosh R et al.. “Standardization of coding definitions for sickle cell disease complications: A systematic literature review.” Pharmacoepidemiology and drug safety (2024). PMID: 39205482 ↗
L1SR_OBSCited in: 1. Definition, Classification & Nomenclature
[14]
Kaufmann GT, Russell M, Shukla P et al.. “Retrospective Cohort Study of Sickle Cell Disease and Large Vessel Retinal Vascular Occlusion Risk in a National United States Database.” Ophthalmology. Retina (2024). PMID: 39033926 ↗
L2COHORTCited in: 1. Definition, Classification & Nomenclature
[15]
Valle J, Lebensburger JD, Garimella PS et al.. “Prevalence, Mortality, and Access to Care for Chronic Kidney Disease in Medicaid-Enrolled Adults With Sickle Cell Disease in California: Retrospective Cohort Study.” JMIR public health and surveillance (2024). PMID: 39008353 ↗
L2COHORTCited in: 1. Definition, Classification & Nomenclature
[16]
Jose A, Bodade A, Madkaikar MR. “Assessing and managing iron deficiency anemia in sickle cell disease: Insights from a systematic review and meta-analysis.” Journal of postgraduate medicine (2025). PMID: 40047486 ↗
L1SR_OBSCited in: 1. Definition, Classification & Nomenclature
[17]
Niihara Y, Miller ST, Kanter J et al.. “A Phase 3 Trial of l-Glutamine in Sickle Cell Disease.” The New England journal of medicine (2018). PMID: 30021096 ↗
L1RCTCited in: 2. Pathophysiology & Mechanism, 3. Epidemiology, Etiology & Risk Factors, 8. Long-term & Definitive Management, History and Evolution of Treatment, 14. Prevention, Screening & Surveillance
[18]
Ataga KI, Kutlar A, Kanter J et al.. “Crizanlizumab for the Prevention of Pain Crises in Sickle Cell Disease.” The New England journal of medicine (2016). PMID: 27959701 ↗
L1RCTCited in: 2. Pathophysiology & Mechanism, 3. Epidemiology, Etiology & Risk Factors, 8. Long-term & Definitive Management, History and Evolution of Treatment, 14. Prevention, Screening & Surveillance
[19]
Vichinsky E, Hoppe CC, Ataga KI et al.. “A Phase 3 Randomized Trial of Voxelotor in Sickle Cell Disease.” The New England journal of medicine (2019). PMID: 31199090 ↗
L1RCTCited in: 2. Pathophysiology & Mechanism, 8. Long-term & Definitive Management, History and Evolution of Treatment
[20]
Tumburu L, Ghosh-Choudhary S, Seifuddin FT et al.. “Circulating mitochondrial DNA is a proinflammatory DAMP in sickle cell disease.” Blood (2021). PMID: 33661274 ↗
L3TRIAL_NONRANDOMCited in: 2. Pathophysiology & Mechanism, 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling, 6. Staging, Risk Stratification & Prognostic Scoring
[21]
Garrett ME, Soldano KL, Erwin KN et al.. “Genome-wide meta-analysis identifies new candidate genes for sickle cell disease nephropathy.” Blood advances (2023). PMID: 36399516 ↗
L2SR_OBSCited in: 2. Pathophysiology & Mechanism, 11. Complications, 12. Prognosis & Natural History
[22]
Olujohungbe A, Burnett AL. “How I manage priapism due to sickle cell disease.” British journal of haematology (2013). PMID: 23293942 ↗
L5TRIAL_NONRANDOMCited in: 2. Pathophysiology & Mechanism, 7. Acute & Emergency Management, 11. Complications, 12. Prognosis & Natural History
[23]
Ribeil JA, Hacein-Bey-Abina S, Payen E et al.. “Gene Therapy in a Patient with Sickle Cell Disease.” The New England journal of medicine (2017). PMID: 28249145 ↗
L4CASE_REPORTCited in: 2. Pathophysiology & Mechanism, 8. Long-term & Definitive Management, 9. Hematopoietic Cell Transplantation & Cellular Therapy
[24]
Steinberg MH. “Fetal hemoglobin in sickle cell anemia.” Blood (2020). PMID: 32808012 ↗
L5REVIEW_NARRATIVECited in: 2. Pathophysiology & Mechanism, 8. Long-term & Definitive Management
[25]
Atiq F, O'Donnell JS. “Novel functions for von Willebrand factor.” Blood (2024). PMID: 38728426 ↗
L5REVIEW_NARRATIVECited in: 2. Pathophysiology & Mechanism
[26]
Li C, Georgakopoulou A, Newby GA et al.. “In vivo HSC prime editing rescues sickle cell disease in a mouse model.” Blood (2023). PMID: 36800642 ↗
L5OTHERCited in: 2. Pathophysiology & Mechanism, 8. Long-term & Definitive Management
[27]
Byrnes JR, Wolberg AS. “Red blood cells in thrombosis.” Blood (2017). PMID: 28811305 ↗
L5REVIEW_NARRATIVECited in: 2. Pathophysiology & Mechanism
[28]
Pinto VM, Mazzi F, De Franceschi L. “Novel therapeutic approaches in thalassemias, sickle cell disease, and other red cell disorders.” Blood (2024). PMID: 38820588 ↗
L5REVIEW_NARRATIVECited in: 2. Pathophysiology & Mechanism, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)
[29]
Sharma R, Antypiuk A, Vance SZ et al.. “Macrophage metabolic rewiring improves heme-suppressed efferocytosis and tissue damage in sickle cell disease.” Blood (2023). PMID: 36952641 ↗
L5OTHERCited in: 2. Pathophysiology & Mechanism
[30]
Han Y, Gao C, Liu Y et al.. “Hemolysis-driven IFNα production impairs erythropoiesis by negatively regulating EPO signaling in sickle cell disease.” Blood (2024). PMID: 38127913 ↗
L5OTHERCited in: 2. Pathophysiology & Mechanism, 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling, 8. Long-term & Definitive Management, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)
[31]
Esoh K, Wonkam-Tingang E, Wonkam A. “Sickle cell disease in sub-Saharan Africa: transferable strategies for prevention and care.” The Lancet. Haematology (2021). PMID: 34481550 ↗
L5REVIEW_NARRATIVECited in: 2. Pathophysiology & Mechanism, 3. Epidemiology, Etiology & Risk Factors, 8. Long-term & Definitive Management, 12. Prognosis & Natural History, 14. Prevention, Screening & Surveillance
[32]
Grunenwald A, Peliconi J, Zarantonello A et al.. “HCAR2 is a novel receptor for heme.” Blood advances (2025). PMID: 40353812 ↗
L5OTHERCited in: 2. Pathophysiology & Mechanism, 14. Prevention, Screening & Surveillance
[33]
Dosunmu-Ogunbi AM, Wood KC, Novelli EM et al.. “Decoding the role of SOD2 in sickle cell disease.” Blood advances (2019). PMID: 31506286 ↗
L5REVIEW_NARRATIVECited in: 2. Pathophysiology & Mechanism
[34]
Adebiyi MG, Manalo JM, Xia Y. “Metabolomic and molecular insights into sickle cell disease and innovative therapies.” Blood advances (2019). PMID: 31015210 ↗
L5REVIEW_NARRATIVECited in: 2. Pathophysiology & Mechanism
[35]
Williams DA, Esrick E. “Investigational curative gene therapy approaches to sickle cell disease.” Blood advances (2021). PMID: 34905048 ↗
L5REVIEW_NARRATIVECited in: 2. Pathophysiology & Mechanism, 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling, 8. Long-term & Definitive Management, 9. Hematopoietic Cell Transplantation & Cellular Therapy
[36]
Lucero MJ, Setua S, Thangaraju K et al.. “Ferroportin inhibition attenuates pulmonary hypertension in hypoxic sickle cell disease mice.” Blood advances (2026). PMID: 41538305 ↗
L5OTHERCited in: 2. Pathophysiology & Mechanism, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)
[37]
Lê BM, Hatch D, Yang Q et al.. “Characterizing epigenetic aging in an adult sickle cell disease cohort.” Blood advances (2024). PMID: 37967379 ↗
L4OTHERCited in: 2. Pathophysiology & Mechanism
[38]
Costa E, Isgrò A, de Montalembert M et al.. “Successes and pitfalls in orphan drug development for sickle cell disease.” Blood advances (2024). PMID: 38522095 ↗
L5OTHERCited in: 2. Pathophysiology & Mechanism, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)
[39]
Rees DC, Williams TN, Gladwin MT. “Sickle-cell disease.” Lancet (London, England) (2010). PMID: 21131035 ↗
L5REVIEW_NARRATIVECited in: 2. Pathophysiology & Mechanism, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), 14. Prevention, Screening & Surveillance
[40]
Ware RE, de Montalembert M, Tshilolo L et al.. “Sickle cell disease.” Lancet (London, England) (2017). PMID: 28159390 ↗
L5REVIEW_NARRATIVECited in: 2. Pathophysiology & Mechanism, 4. Clinical Presentation, 8. Long-term & Definitive Management, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), 12. Prognosis & Natural History, 13. Special Populations & Pregnancy, 14. Prevention, Screening & Surveillance
[41]
Colombatti R, Jastaniah W, Makani J et al.. “Sickle cell disease.” Lancet (London, England) (2026). PMID: 41831848 ↗
L5REVIEW_NARRATIVECited in: 2. Pathophysiology & Mechanism, 8. Long-term & Definitive Management, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), 11. Complications, 13. Special Populations & Pregnancy, 14. Prevention, Screening & Surveillance
[42]
Gladwin MT. “Cardiovascular complications and risk of death in sickle-cell disease.” Lancet (London, England) (2016). PMID: 27353687 ↗
L5REVIEW_NARRATIVECited in: 2. Pathophysiology & Mechanism, 3. Epidemiology, Etiology & Risk Factors, 12. Prognosis & Natural History, 14. Prevention, Screening & Surveillance
[43]
Carden MA, Little J. “Emerging disease-modifying therapies for sickle cell disease.” Haematologica (2019). PMID: 31413089 ↗
L5REVIEW_NARRATIVECited in: 2. Pathophysiology & Mechanism, 8. Long-term & Definitive Management, 9. Hematopoietic Cell Transplantation & Cellular Therapy
[44]
Saunthararajah Y. “Targeting sickle cell disease root-cause pathophysiology with small molecules.” Haematologica (2019). PMID: 31399526 ↗
L5REVIEW_NARRATIVECited in: 2. Pathophysiology & Mechanism
[45]
Allali S, Maciel TT, Hermine O et al.. “Innate immune cells, major protagonists of sickle cell disease pathophysiology.” Haematologica (2020). PMID: 31919091 ↗
L5REVIEW_NARRATIVECited in: 2. Pathophysiology & Mechanism
[46]
Conran N, De Paula EV. “Thromboinflammatory mechanisms in sickle cell disease - challenging the hemostatic balance.” Haematologica (2020). PMID: 33054078 ↗
L5OTHERCited in: 2. Pathophysiology & Mechanism, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), 12. Prognosis & Natural History
[47]
Lizarralde-Iragorri MA, Lefevre SD, Cochet S et al.. “Oxidative stress activates red cell adhesion to laminin in sickle cell disease.” Haematologica (2021). PMID: 32855277 ↗
L3OTHERCited in: 2. Pathophysiology & Mechanism, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)
[48]
Brandsen RP, Diederen RMH, Kocabas G et al.. “Clinical and laboratory risk factors for sickle cell retinopathy and maculopathy: a scoping review of the current evidence.” Haematologica (2024). PMID: 39704162 ↗
L5REVIEW_NARRATIVECited in: 2. Pathophysiology & Mechanism, 14. Prevention, Screening & Surveillance
[49]
Kaminski TW, Katoch O, Li Z et al.. “Impaired hemoglobin clearance by sinusoidal endothelium promotes vaso-occlusion and liver injury in sickle cell disease.” Haematologica (2024). PMID: 37941440 ↗
L5OTHERCited in: 2. Pathophysiology & Mechanism
[50]
Schimmel M, Nur E, Biemond BJ et al.. “Nucleosomes and neutrophil activation in sickle cell disease painful crisis.” Haematologica (2013). PMID: 23911704 ↗
L2OTHERCited in: 2. Pathophysiology & Mechanism
[51]
Pace BS, Starlard-Davenport A, Kutlar A. “Sickle cell disease: progress towards combination drug therapy.” British journal of haematology (2021). PMID: 33471938 ↗
L5REVIEW_NARRATIVECited in: 2. Pathophysiology & Mechanism, 8. Long-term & Definitive Management, History and Evolution of Treatment, 12. Prognosis & Natural History
[52]
Rees DC, Gibson JS. “Biomarkers in sickle cell disease.” British journal of haematology (2011). PMID: 22122125 ↗
L5REVIEW_NARRATIVECited in: 2. Pathophysiology & Mechanism, 6. Staging, Risk Stratification & Prognostic Scoring
[53]
Paikari A, Sheehan VA. “Fetal haemoglobin induction in sickle cell disease.” British journal of haematology (2017). PMID: 29143315 ↗
L5REVIEW_NARRATIVECited in: 2. Pathophysiology & Mechanism, 8. Long-term & Definitive Management, 9. Hematopoietic Cell Transplantation & Cellular Therapy
[54]
Gupta CL, Jaganathasamy N, Madkaikar M. “Microbiome in sickle cell disease: Pathophysiology and therapeutic insights.” British journal of haematology (2024). PMID: 39206530 ↗
L5REVIEW_NARRATIVECited in: 2. Pathophysiology & Mechanism
[55]
Piccin A, O'Connor-Byrne N, Daves M et al.. “Autoimmune disease and sickle cell anaemia: 'Intersecting pathways and differential diagnosis'.” British journal of haematology (2022). PMID: 35244209 ↗
L5REVIEW_NARRATIVECited in: 2. Pathophysiology & Mechanism, 4. Clinical Presentation, 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling, 8. Long-term & Definitive Management
[56]
Wilson S, Ellsworth P, Key NS. “Pregnancy in sickle cell trait: what we do and don't know.” British journal of haematology (2020). PMID: 32064587 ↗
L5REVIEW_NARRATIVECited in: 2. Pathophysiology & Mechanism, 13. Special Populations & Pregnancy
[57]
Catella J, Guillot N, Nader E et al.. “Controversies in the pathophysiology of leg ulcers in sickle cell disease.” British journal of haematology (2024). PMID: 38867511 ↗
L5REVIEW_NARRATIVECited in: 2. Pathophysiology & Mechanism
[58]
Sparkenbaugh E, Pawlinski R. “Prothrombotic aspects of sickle cell disease.” Journal of thrombosis and haemostasis : JTH (2017). PMID: 28671346 ↗
L5REVIEW_NARRATIVECited in: 2. Pathophysiology & Mechanism, 8. Long-term & Definitive Management, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)
[59]
Sparkenbaugh EM, Kasztan M, Henderson MW et al.. “High molecular weight kininogen contributes to early mortality and kidney dysfunction in a mouse model of sickle cell disease.” Journal of thrombosis and haemostasis : JTH (2020). PMID: 32573897 ↗
L5OTHERCited in: 2. Pathophysiology & Mechanism, 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling, 12. Prognosis & Natural History
[60]
Sins JWR, Schimmel M, Luken BM et al.. “Dynamics of von Willebrand factor reactivity in sickle cell disease during vaso-occlusive crisis and steady state.” Journal of thrombosis and haemostasis : JTH (2017). PMID: 28457019 ↗
L2OTHERCited in: 2. Pathophysiology & Mechanism, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), 11. Complications
[61]
Al-Subaie AM, Borgio JF. “Systematic Review of Non-Coding Genomic Variants in Globin and Non-Globin Clusters and Their Impact on Phenotypic Severity in Thalassemia and Sickle Cell Disease.” Journal of clinical medicine (2026). PMID: 41753033 ↗
L5SR_OBSCited in: 2. Pathophysiology & Mechanism, 4. Clinical Presentation, 6. Staging, Risk Stratification & Prognostic Scoring
[62]
Simo JL, Tuono RM, Yong IWS et al.. “Complete Blood Count Profile in Steady State Sickle Cell Disease Patient: A Systematic Review and Meta-Analysis.” Health science reports (2026). PMID: 42022594 ↗
L2SR_OBSCited in: 2. Pathophysiology & Mechanism, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)
[63]
Simo JL, Tuono RM, Njopwouo MS et al.. “Oxidative Stress, Antioxidant Capacity, Dyslipidemia and Cardiovascular Risk in Sickle Cell Disease: A Systematic Review and Meta-Analysis.” TheScientificWorldJournal (2026). PMID: 41821306 ↗
L2SR_OBSCited in: 2. Pathophysiology & Mechanism
[64]
Simo JL, Angandji PT, Tuono RM et al.. “Hepatic Enzyme Abnormalities and Their Association With Hematological Parameters in Sickle Cell Disease: A Case-Control Study in Cameroon.” Health science reports (2026). PMID: 42291724 ↗
L3CASE_CONTROLCited in: 2. Pathophysiology & Mechanism, 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling
[65]
Wood KC, Nouraie SM, Gladwin MT et al.. “The CYB5R3 T117S Missense Variant is Associated with Attenuated Riociguat Efficacy in Sickle Cell Disease.” Blood (2026). PMID: 42418684 ↗
L2OTHERCited in: 2. Pathophysiology & Mechanism
[66]
Martin OY, Darbari DS. “Pain in SCD-Many mechanisms and mysteries.” Seminars in hematology (2026). PMID: 42392892 ↗
L5OTHERCited in: 2. Pathophysiology & Mechanism, 8. Long-term & Definitive Management
[67]
Weeks LD. “Clonal hematopoiesis in the setting of sickle cell disease and its relevance to curative therapies.” Seminars in hematology (2026). PMID: 42373375 ↗
L5OTHERCited in: 2. Pathophysiology & Mechanism
[68]
Sufian S. “Menopause in rare diseases: Shared research concerns and the case for a dedicated subfield.” Maturitas (2026). PMID: 42308878 ↗
L5REVIEW_NARRATIVECited in: 2. Pathophysiology & Mechanism
[69]
Heeney MM, Abboud MR, Githanga J et al.. “Ticagrelor vs placebo for the reduction of vaso-occlusive crises in pediatric sickle cell disease: the HESTIA3 study.” Blood (2022). PMID: 35849650 ↗
L1RCTCited in: 3. Epidemiology, Etiology & Risk Factors, 7. Acute & Emergency Management, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), History and Evolution of Treatment, 13. Special Populations & Pregnancy
[70]
Abboud MR, Cançado RD, De Montalembert M et al.. “Crizanlizumab with or without hydroxyurea in patients with sickle cell disease (STAND): primary analyses from a placebo-controlled, randomised, double-blind, phase 3 trial.” The Lancet. Haematology (2025). PMID: 40088922 ↗
L1RCTCited in: 3. Epidemiology, Etiology & Risk Factors, 8. Long-term & Definitive Management, History and Evolution of Treatment
[71]
Howard J, Ataga KI, Brown RC et al.. “Voxelotor in adolescents and adults with sickle cell disease (HOPE): long-term follow-up results of an international, randomised, double-blind, placebo-controlled, phase 3 trial.” The Lancet. Haematology (2021). PMID: 33838113 ↗
L1RCTCited in: 3. Epidemiology, Etiology & Risk Factors, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), History and Evolution of Treatment
[72]
Austin H, Key NS, Benson JM et al.. “Sickle cell trait and the risk of venous thromboembolism among blacks.” Blood (2007). PMID: 17409269 ↗
L3TRIAL_NONRANDOMCited in: 3. Epidemiology, Etiology & Risk Factors
[73]
Yuditskaya S, Tumblin A, Hoehn GT et al.. “Proteomic identification of altered apolipoprotein patterns in pulmonary hypertension and vasculopathy of sickle cell disease.” Blood (2008). PMID: 19023114 ↗
L3TRIAL_NONRANDOMCited in: 3. Epidemiology, Etiology & Risk Factors
[74]
Shenoy S, Eapen M, Panepinto JA et al.. “A trial of unrelated donor marrow transplantation for children with severe sickle cell disease.” Blood (2016). PMID: 27625358 ↗
L2TRIAL_NONRANDOMCited in: 3. Epidemiology, Etiology & Risk Factors, 9. Hematopoietic Cell Transplantation & Cellular Therapy
[75]
Oteng-Ntim E, Oakley LL, Robinson V et al.. “Prophylactic exchange transfusion in sickle cell disease pregnancy: a TAPS2 feasibility randomized controlled trial.” Blood advances (2024). PMID: 38954844 ↗
L1RCTCited in: 3. Epidemiology, Etiology & Risk Factors, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), History and Evolution of Treatment, 13. Special Populations & Pregnancy
[76]
Goldenberg M, Varadhan R, Gamper CJ et al.. “Bone marrow transplantation for sickle cell disease using posttransplantation cyclophosphamide and 400 cGy TBI.” Blood advances (2026). PMID: 41569644 ↗
L4TRIAL_NONRANDOMCited in: 3. Epidemiology, Etiology & Risk Factors, 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling, 8. Long-term & Definitive Management, 9. Hematopoietic Cell Transplantation & Cellular Therapy, 11. Complications, 12. Prognosis & Natural History
[77]
Parikh S, Brochstein JA, Galamidi E et al.. “Allogeneic stem cell transplantation with omidubicel in sickle cell disease.” Blood advances (2021). PMID: 33560399 ↗
L4TRIAL_NONRANDOMCited in: 3. Epidemiology, Etiology & Risk Factors, 9. Hematopoietic Cell Transplantation & Cellular Therapy, 13. Special Populations & Pregnancy
[78]
Lamarre Y, Romana M, Waltz X et al.. “Hemorheological risk factors of acute chest syndrome and painful vaso-occlusive crisis in children with sickle cell disease.” Haematologica (2012). PMID: 22689686 ↗
L2TRIAL_NONRANDOMCited in: 3. Epidemiology, Etiology & Risk Factors, History and Evolution of Treatment
[79]
Jacobs JW, Stephens LD, Allen ES et al.. “Epidemiological and clinical features, therapeutic strategies and outcomes in patients with hyperhaemolysis: A systematic review.” British journal of haematology (2023). PMID: 37074146 ↗
L4SR_OBSCited in: 3. Epidemiology, Etiology & Risk Factors, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)
[80]
Shet AS, Wun T. “How I diagnose and treat venous thromboembolism in sickle cell disease.” Blood (2018). PMID: 29764840 ↗
L5CASE_REPORTCited in: 3. Epidemiology, Etiology & Risk Factors, 4. Clinical Presentation, 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling, 6. Staging, Risk Stratification & Prognostic Scoring
[81]
Scott JA, Berkley JA, Mwangi I et al.. “Relation between falciparum malaria and bacteraemia in Kenyan children: a population-based, case-control study and a longitudinal study.” Lancet (London, England) (2011). PMID: 21903251 ↗
L3CASE_CONTROLCited in: 3. Epidemiology, Etiology & Risk Factors, 11. Complications
[82]
Novelli EM, Huynh C, Gladwin MT et al.. “Pulmonary embolism in sickle cell disease: a case-control study.” Journal of thrombosis and haemostasis : JTH (2012). PMID: 22417249 ↗
L3CASE_CONTROLCited in: 3. Epidemiology, Etiology & Risk Factors, 12. Prognosis & Natural History
[83]
Smith-Whitley K. “Reproductive issues in sickle cell disease.” Blood (2014). PMID: 25472967 ↗
L5REVIEW_NARRATIVECited in: 3. Epidemiology, Etiology & Risk Factors, 8. Long-term & Definitive Management, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)
[84]
Pecker LH, Naik RP. “The current state of sickle cell trait: implications for reproductive and genetic counseling.” Blood (2018). PMID: 30487130 ↗
L5REVIEW_NARRATIVECited in: 3. Epidemiology, Etiology & Risk Factors, 14. Prevention, Screening & Surveillance
[85]
Piel FB, Rees DC, DeBaun MR et al.. “Defining global strategies to improve outcomes in sickle cell disease: a Lancet Haematology Commission.” The Lancet. Haematology (2023). PMID: 37451304 ↗
L5REVIEW_NARRATIVECited in: 3. Epidemiology, Etiology & Risk Factors, 8. Long-term & Definitive Management, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), 11. Complications, 12. Prognosis & Natural History, 14. Prevention, Screening & Surveillance
[86]
Mañú Pereira MDM, Colombatti R, Alvarez F et al.. “Sickle cell disease landscape and challenges in the EU: the ERN-EuroBloodNet perspective.” The Lancet. Haematology (2023). PMID: 37451300 ↗
L5REVIEW_NARRATIVECited in: 3. Epidemiology, Etiology & Risk Factors
[87]
Allen ES, Srivastava K, Hsieh MM et al.. “Immunohaematological complications in patients with sickle cell disease after haemopoietic progenitor cell transplantation: a prospective, single-centre, observational study.” The Lancet. Haematology (2017). PMID: 29100558 ↗
L2OTHERCited in: 3. Epidemiology, Etiology & Risk Factors, 9. Hematopoietic Cell Transplantation & Cellular Therapy, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)
[88]
DeBaun MR, Strunk RC. “The intersection between asthma and acute chest syndrome in children with sickle-cell anaemia.” Lancet (London, England) (2016). PMID: 27353685 ↗
L5CASE_REPORTCited in: 3. Epidemiology, Etiology & Risk Factors, 4. Clinical Presentation
[89]
Dorfman SR, Chan SS, Amanullah S et al.. “ACR Appropriateness Criteria® Chest Pain-Child.” Journal of the American College of Radiology : JACR (2026). PMID: 41729147 ↗
L1GUIDELINECited in: 3. Epidemiology, Etiology & Risk Factors, 7. Acute & Emergency Management, History and Evolution of Treatment
[90]
Eapen M, Brazauskas R, Williams DA et al.. “Secondary Neoplasms After Hematopoietic Cell Transplant for Sickle Cell Disease.” Journal of clinical oncology : official journal of the American Society of Clinical Oncology (2023). PMID: 36623245 ↗
L2OTHERCited in: 3. Epidemiology, Etiology & Risk Factors, 9. Hematopoietic Cell Transplantation & Cellular Therapy
[91]
Sinha U, Setty S, Pilon C et al.. “Systemic lupus erythematosus-associated autoantibodies in sickle cell disease: Spontaneous emergence in a patient and in transgenic sickle mice.” British journal of haematology (2025). PMID: 39748216 ↗
L4CASE_REPORTCited in: 3. Epidemiology, Etiology & Risk Factors
[92]
Patwardhan AA, Patel A, Pasupuleti A et al.. “Use of the microfluidic impedance red cell assay in sickle cell disease.” Blood advances (2025). PMID: 40311069 ↗
L4OTHERCited in: 3. Epidemiology, Etiology & Risk Factors, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), 13. Special Populations & Pregnancy
[93]
Kumari N, Ammosova T, Diaz S et al.. “Increased iron export by ferroportin induces restriction of HIV-1 infection in sickle cell disease.” Blood advances (2016). PMID: 28203649 ↗
L5OTHERCited in: 3. Epidemiology, Etiology & Risk Factors
[94]
Schoettler M, Stenger E, Spencer K et al.. “Sickle cell disease is a risk factor for transplant-associated thrombotic microangiopathy in children.” Blood advances (2023). PMID: 36075028 ↗
L2OTHERCited in: 3. Epidemiology, Etiology & Risk Factors, 9. Hematopoietic Cell Transplantation & Cellular Therapy, 14. Prevention, Screening & Surveillance
[95]
Lettre G, Bauer DE. “Fetal haemoglobin in sickle-cell disease: from genetic epidemiology to new therapeutic strategies.” Lancet (London, England) (2016). PMID: 27353686 ↗
L5REVIEW_NARRATIVECited in: 3. Epidemiology, Etiology & Risk Factors, 8. Long-term & Definitive Management
[96]
Afolabi BB, Babah OA, Oshodi YA et al.. “Low-dose aspirin for preventing intrauterine growth restriction and pre-eclampsia in sickle cell pregnancy in Nigeria (PIPSICKLE): a randomised controlled trial.” The Lancet. Global health (2026). PMID: 41713441 ↗
L1RCTCited in: 3. Epidemiology, Etiology & Risk Factors, History and Evolution of Treatment
[97]
Brousse V, Bernaudin F, Melaine A et al.. “Severity and burden of sickle cell disease in France: a nationwide real-world study.” Haematologica (2023). PMID: 36924235 ↗
L2OTHERCited in: 3. Epidemiology, Etiology & Risk Factors, 8. Long-term & Definitive Management, 9. Hematopoietic Cell Transplantation & Cellular Therapy, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)
[98]
Linguet SL, Verlhac S, Missud F et al.. “Stroke without cerebral arteriopathy in sickle cell disease children: causes and treatment.” Haematologica (2024). PMID: 38497171 ↗
L2OTHERCited in: 3. Epidemiology, Etiology & Risk Factors, 8. Long-term & Definitive Management, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), 13. Special Populations & Pregnancy, 14. Prevention, Screening & Surveillance
[99]
Day TG, Drasar ER, Fulford T et al.. “Association between hemolysis and albuminuria in adults with sickle cell anemia.” Haematologica (2011). PMID: 21993677 ↗
L2OTHERCited in: 3. Epidemiology, Etiology & Risk Factors
[100]
Evans C, Orf K, Horvath E et al.. “Impairment of neutrophil oxidative burst in children with sickle cell disease is associated with heme oxygenase-1.” Haematologica (2015). PMID: 26315932 ↗
L3OTHERCited in: 3. Epidemiology, Etiology & Risk Factors
[101]
Nouraie M, Lee JS, Zhang Y et al.. “The relationship between the severity of hemolysis, clinical manifestations and risk of death in 415 patients with sickle cell anemia in the US and Europe.” Haematologica (2012). PMID: 22983573 ↗
L4OTHERCited in: 3. Epidemiology, Etiology & Risk Factors, 6. Staging, Risk Stratification & Prognostic Scoring
[102]
Chaar V, Picot J, Renaud O et al.. “Aggregation of mononuclear and red blood cells through an {alpha}4{beta}1-Lu/basal cell adhesion molecule interaction in sickle cell disease.” Haematologica (2010). PMID: 20562314 ↗
L3OTHERCited in: 3. Epidemiology, Etiology & Risk Factors
[103]
Loh J, Kuo KHM, Georgescu I et al.. “Risk factors for immediate postpartum sickle cell disease-specific maternal morbidity.” British journal of haematology (2025). PMID: 40462503 ↗
L4OTHERCited in: 3. Epidemiology, Etiology & Risk Factors, 11. Complications, 12. Prognosis & Natural History, 13. Special Populations & Pregnancy
[104]
Cseh A, Galimard JE, de la Fuente J et al.. “Busulfan-fludarabine- or treosulfan-fludarabine-based conditioning before allogeneic HSCT from matched sibling donors in paediatric patients with sickle cell disease: A study on behalf of the EBMT Paediatric Diseases and Inborn Errors Working Parties.” British journal of haematology (2023). PMID: 37795523 ↗
L2OTHERCited in: 3. Epidemiology, Etiology & Risk Factors, 9. Hematopoietic Cell Transplantation & Cellular Therapy
[105]
Brousse V, Kossorotoff M, de Montalembert M. “How I manage cerebral vasculopathy in children with sickle cell disease.” British journal of haematology (2015). PMID: 25944412 ↗
L5REVIEW_NARRATIVECited in: 3. Epidemiology, Etiology & Risk Factors, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)
[106]
Wilson SR, Noubouossie D, Little JA et al.. “Real-world assessment of acute red cell exchange for stroke in sickle cell disease.” British journal of haematology (2025). PMID: 40415245 ↗
L4OTHERCited in: 3. Epidemiology, Etiology & Risk Factors, 7. Acute & Emergency Management, History and Evolution of Treatment
[107]
El-Amin N, Lauzon SD, Nietert PJ et al.. “Which adults with sickle cell disease need an evaluation for pulmonary embolism?” British journal of haematology (2021). PMID: 34472094 ↗
L4OTHERCited in: 3. Epidemiology, Etiology & Risk Factors, 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling
[108]
Campbell AIK, Xu Y, Skeith L et al.. “Racial and ethnic disparities in eligibility for postpartum venous thromboembolism prophylaxis in the United States.” Journal of thrombosis and haemostasis : JTH (2023). PMID: 37838240 ↗
L2OTHERCited in: 3. Epidemiology, Etiology & Risk Factors, 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), History and Evolution of Treatment, 13. Special Populations & Pregnancy
[109]
Whelihan MF, Lim MY, Mooberry MJ et al.. “Thrombin generation and cell-dependent hypercoagulability in sickle cell disease.” Journal of thrombosis and haemostasis : JTH (2016). PMID: 27430959 ↗
L3OTHERCited in: 3. Epidemiology, Etiology & Risk Factors
[110]
O'Toole G, Swan D, Connors JM et al.. “Hematological causes of acute ischemic stroke in younger individuals.” Journal of thrombosis and haemostasis : JTH (2024). PMID: 39393779 ↗
L5REVIEW_NARRATIVECited in: 3. Epidemiology, Etiology & Risk Factors, 8. Long-term & Definitive Management, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), 12. Prognosis & Natural History
[111]
Naik RP, Streiff MB, Haywood C et al.. “Venous thromboembolism incidence in the Cooperative Study of Sickle Cell Disease.” Journal of thrombosis and haemostasis : JTH (2014). PMID: 25280124 ↗
L2OTHERCited in: 3. Epidemiology, Etiology & Risk Factors, 11. Complications, 12. Prognosis & Natural History
[112]
Alvarez OA, Lerebours E, Paul Hanna M et al.. “Baseline Characteristics and Social Challenges of Children with Sickle Cell Disease in Haiti and after Immigration to the United States: A Comparative Cohort Study.” Journal of racial and ethnic health disparities (2026). PMID: 42323490 ↗
L2COHORTCited in: 3. Epidemiology, Etiology & Risk Factors, 8. Long-term & Definitive Management
[113]
Hayford K, Tort MJ, Huang L et al.. “Clinical effectiveness and impact of 13-valent pneumococcal conjugate vaccines in preventing invasive pneumococcal disease among children with risk conditions: A systematic literature review.” Human vaccines & immunotherapeutics (2026). PMID: 41560367 ↗
L2SR_OBSCited in: 3. Epidemiology, Etiology & Risk Factors
[114]
de Almeida Barros VM, Silva-Pinto AC, Moura PG et al.. “Risk of vaso-occlusive crisis requiring hospitalization in sickle cell disease patients in brazil: retrospective cohort study of real-world data.” Annals of hematology (2026). PMID: 41711948 ↗
L2COHORTCited in: 3. Epidemiology, Etiology & Risk Factors, 7. Acute & Emergency Management
[115]
Gladwin MT, Gordeuk VR, Desai PC et al.. “Riociguat in patients with sickle cell disease and hypertension or proteinuria (STERIO-SCD): a randomised, double-blind, placebo controlled, phase 1-2 trial.” The Lancet. Haematology (2024). PMID: 38554715 ↗
L1RCTCited in: 4. Clinical Presentation, 8. Long-term & Definitive Management, History and Evolution of Treatment, 12. Prognosis & Natural History
[116]
Mahlangu J, Colombatti R, James J et al.. “Motivators and barriers affecting decisions to participate in sickle cell disease clinical trials in the global Learning and Insights into Sickle Cell Trial Experiences (LISTEN) Survey: global and regional findings.” The Lancet. Haematology (2025). PMID: 41338865 ↗
L4TRIAL_NONRANDOMCited in: 4. Clinical Presentation
[117]
Jonassaint CR, Lalama CM, Carroll CP et al.. “Digital cognitive behavioral therapy vs education for pain in adults with sickle cell disease.” Blood advances (2024). PMID: 39374587 ↗
L1RCTCited in: 4. Clinical Presentation, 8. Long-term & Definitive Management, History and Evolution of Treatment, 12. Prognosis & Natural History
[118]
Lee LH, Whisenton LH, Benger J et al.. “A community-centered approach to sickle cell disease and clinical trial participation: an evaluation of perceptions, facilitators, and barriers.” Blood advances (2021). PMID: 34543385 ↗
L4TRIAL_NONRANDOMCited in: 4. Clinical Presentation
[119]
Jonassaint CR, Jones VL, Leong S et al.. “A systematic review of the association between depression and health care utilization in children and adults with sickle cell disease.” British journal of haematology (2016). PMID: 26991317 ↗
L2SR_OBSCited in: 4. Clinical Presentation, 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling
[120]
Oligbu G, Fallaha M, Pay L et al.. “Risk of invasive pneumococcal disease in children with sickle cell disease in the era of conjugate vaccines: a systematic review of the literature.” British journal of haematology (2019). PMID: 30859558 ↗
L2SR_OBSCited in: 4. Clinical Presentation, 11. Complications
[121]
Rossi M, Pirenne F, Le Roux E et al.. “Delayed haemolytic transfusion reaction in paediatric patients with sickle cell disease: A retrospective study in a French national reference centre.” British journal of haematology (2022). PMID: 36541848 ↗
L4COHORTCited in: 4. Clinical Presentation
[122]
Thein SL, Howard J. “How I treat the older adult with sickle cell disease.” Blood (2018). PMID: 30206116 ↗
L5CASE_REPORTCited in: 4. Clinical Presentation, 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling, 12. Prognosis & Natural History
[123]
Pirenne F, Yazdanbakhsh K. “How I safely transfuse patients with sickle-cell disease and manage delayed hemolytic transfusion reactions.” Blood (2018). PMID: 29724898 ↗
L5CASE_REPORTCited in: 4. Clinical Presentation, 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling
[124]
Machogu EM, Machado RF. “How I treat hypoxia in adults with hemoglobinopathies and hemolytic disorders.” Blood (2018). PMID: 30206115 ↗
L5CASE_REPORTCited in: 4. Clinical Presentation, History and Evolution of Treatment
[125]
Sharpe CC, Thein SL. “How I treat renal complications in sickle cell disease.” Blood (2014). PMID: 24764565 ↗
L5CASE_REPORTCited in: 4. Clinical Presentation
[126]
Xi C, Pang J, Zhi W et al.. “Nrf2 sensitizes ferroptosis through l-2-hydroxyglutarate-mediated chromatin modifications in sickle cell disease.” Blood (2023). PMID: 37267508 ↗
L5OTHERCited in: 4. Clinical Presentation
[127]
Miller ST. “How I treat acute chest syndrome in children with sickle cell disease.” Blood (2011). PMID: 21406723 ↗
L5REVIEW_NARRATIVECited in: 4. Clinical Presentation, 11. Complications
[128]
Calis JC, Phiri KS, Faragher EB et al.. “Severe anemia in Malawian children.” The New England journal of medicine (2008). PMID: 18305266 ↗
L3OTHERCited in: 4. Clinical Presentation, 11. Complications
[129]
Noizat-Pirenne F, Bachir D, Chadebech P et al.. “Rituximab for prevention of delayed hemolytic transfusion reaction in sickle cell disease.” Haematologica (2007). PMID: 18055978 ↗
L4CASE_REPORTCited in: 4. Clinical Presentation, 11. Complications, 14. Prevention, Screening & Surveillance
[130]
Gardner K, Hoppe C, Mijovic A et al.. “How we treat delayed haemolytic transfusion reactions in patients with sickle cell disease.” British journal of haematology (2015). PMID: 25967919 ↗
L5CASE_REPORTCited in: 4. Clinical Presentation
[131]
Gonzalez Sepulveda JM, Yang JC, Reed SD et al.. “Preferences for potential benefits and risks for gene therapy in the treatment of sickle cell disease.” Blood advances (2023). PMID: 37905989 ↗
L2OTHERCited in: 4. Clinical Presentation
[132]
Agawu A, Nortey N, Jacobs C et al.. “Respiratory phenotype and health care utilization patterns by adults with sickle cell disease.” Blood advances (2025). PMID: 39368809 ↗
L2OTHERCited in: 4. Clinical Presentation, 7. Acute & Emergency Management
[133]
Messimeris D, Bismuth H, Provost C et al.. “Determinants of cognitive dysfunction in adults with sickle cell-related stroke or suspected neurological morbidity.” Blood advances (2024). PMID: 38815229 ↗
L4OTHERCited in: 4. Clinical Presentation
[134]
Ibanez V, Vaitkus K, Zhang X et al.. “Combinatorial targeting of epigenome-modifying enzymes with decitabine and RN-1 synergistically increases HbF.” Blood advances (2023). PMID: 36884303 ↗
L5OTHERCited in: 4. Clinical Presentation
[135]
Adam SS, Flahiff CM, Kamble S et al.. “Depression, quality of life, and medical resource utilization in sickle cell disease.” Blood advances (2017). PMID: 29296845 ↗
L2OTHERCited in: 4. Clinical Presentation
[136]
Piel FB, Tewari S, Brousse V et al.. “Associations between environmental factors and hospital admissions for sickle cell disease.” Haematologica (2016). PMID: 27909222 ↗
L2OTHERCited in: 4. Clinical Presentation
[137]
Tewari S, Brousse V, Piel FB et al.. “Environmental determinants of severity in sickle cell disease.” Haematologica (2015). PMID: 26341524 ↗
L5REVIEW_NARRATIVECited in: 4. Clinical Presentation, 11. Complications
[138]
D'Alessandro A, Nouraie SM, Zhang Y et al.. “Metabolic signatures of cardiorenal dysfunction in plasma from sickle cell patients as a function of therapeutic transfusion and hydroxyurea treatment.” Haematologica (2023). PMID: 37439373 ↗
L2OTHERCited in: 4. Clinical Presentation, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), History and Evolution of Treatment
[139]
Pellegrin S, Severn CE, Toye AM. “Towards manufactured red blood cells for the treatment of inherited anemia.” Haematologica (2021). PMID: 34042406 ↗
L5REVIEW_NARRATIVECited in: 4. Clinical Presentation, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)
[140]
de Montalembert M, Dumont MD, Heilbronner C et al.. “Delayed hemolytic transfusion reaction in children with sickle cell disease.” Haematologica (2011). PMID: 21330322 ↗
L4OTHERCited in: 4. Clinical Presentation, 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), 13. Special Populations & Pregnancy
[141]
Rivers A, Vaitkus K, Ibanez V et al.. “The LSD1 inhibitor RN-1 recapitulates the fetal pattern of hemoglobin synthesis in baboons (P. anubis).” Haematologica (2016). PMID: 26858356 ↗
L5OTHERCited in: 4. Clinical Presentation
[142]
Trompeter S, Roberts I. “Haemoglobin F modulation in childhood sickle cell disease.” British journal of haematology (2008). PMID: 19036119 ↗
L5REVIEW_NARRATIVECited in: 4. Clinical Presentation, 8. Long-term & Definitive Management, History and Evolution of Treatment
[143]
Rees DC, Robinson S, Howard J. “How I manage red cell transfusions in patients with sickle cell disease.” British journal of haematology (2018). PMID: 29377071 ↗
L5REVIEW_NARRATIVECited in: 4. Clinical Presentation, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), 13. Special Populations & Pregnancy, 14. Prevention, Screening & Surveillance
[144]
van der Meer M, Velsink K, Tong WH et al.. “Is There a Difference in Occurrence of Complications Between Adults With Hemoglobin SS and Hemoglobin SC Disease: An Extended Systematic Review.” European journal of haematology (2026). PMID: 42297565 ↗
L2SR_OBSCited in: 4. Clinical Presentation, 11. Complications, 14. Prevention, Screening & Surveillance
[145]
Paris J, Almater AI, Mackenzie C et al.. “Orbital involvement in sickle cell disease: A systematic review.” Survey of ophthalmology (2026). PMID: 42235647 ↗
L4SR_OBSCited in: 4. Clinical Presentation, 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling
[146]
Molena KF, Costa MA, Paulo AC et al.. “High prevalence of molar-incisor hypomineralisation in sickle cell disease children and the association with haematologic profile: a retrospective cohort study.” European archives of paediatric dentistry : official journal of the European Academy of Paediatric Dentistry (2026). PMID: 42313255 ↗
L2COHORTCited in: 4. Clinical Presentation
[147]
Rodgers-Melnick SN, Gunzler D, Love TE et al.. “Longitudinal effects of inpatient music therapy dosage on pain intensity and opioid utilization among patients with hematologic or oncologic conditions: a retrospective cohort study.” Supportive care in cancer : official journal of the Multinational Association of Supportive Care in Cancer (2026). PMID: 42249214 ↗
L2COHORTCited in: 4. Clinical Presentation, 8. Long-term & Definitive Management
[148]
Álvarez-Pérez Y, Duarte-Díaz A, Rivero-Santana A et al.. “Effectiveness of psychological interventions for children eligible for pediatric palliative care: systematic review and meta-analysis.” BMC pediatrics (2026). PMID: 41645150 ↗
L1SR_OBSCited in: 4. Clinical Presentation
[149]
Idowu M, Otieno L, Dumitriu B et al.. “Safety and efficacy of mitapivat in sickle cell disease (RISE UP): results from the phase 2 portion of a global, double-blind, randomised, placebo-controlled trial.” The Lancet. Haematology (2024). PMID: 39644907 ↗
L1RCTCited in: 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling, 8. Long-term & Definitive Management, History and Evolution of Treatment, 12. Prognosis & Natural History
[150]
Biemond BJ, Tombak A, Kilinc Y et al.. “Sevuparin for the treatment of acute pain crisis in patients with sickle cell disease: a multicentre, randomised, double-blind, placebo-controlled, phase 2 trial.” The Lancet. Haematology (2021). PMID: 33894169 ↗
L1RCTCited in: 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling, 8. Long-term & Definitive Management, History and Evolution of Treatment, 11. Complications
[151]
Liem RI, Lanzkron S, D Coates T et al.. “American Society of Hematology 2019 guidelines for sickle cell disease: cardiopulmonary and kidney disease.” Blood advances (2019). PMID: 31794601 ↗
L1GUIDELINECited in: 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), History and Evolution of Treatment, 14. Prevention, Screening & Surveillance
[152]
Kassim AA, de la Fuente J, Nur E et al.. “An international learning collaborative phase 2 trial for haploidentical bone marrow transplant in sickle cell disease.” Blood (2024). PMID: 38493482 ↗
L4TRIAL_NONRANDOMCited in: 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling, 8. Long-term & Definitive Management, 9. Hematopoietic Cell Transplantation & Cellular Therapy, 12. Prognosis & Natural History
[153]
Bolaños-Meade J, Cooke KR, Gamper CJ et al.. “Effect of increased dose of total body irradiation on graft failure associated with HLA-haploidentical transplantation in patients with severe haemoglobinopathies: a prospective clinical trial.” The Lancet. Haematology (2019). PMID: 30878319 ↗
L4TRIAL_NONRANDOMCited in: 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling, 9. Hematopoietic Cell Transplantation & Cellular Therapy, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), History and Evolution of Treatment
[154]
Weeks LD, Wilson AM, Naik RP et al.. “Sickle cell trait does not cause "sickle cell crisis" leading to exertion-related death: a systematic review.” Blood (2025). PMID: 39882975 ↗
L2SR_OBSCited in: 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling, 12. Prognosis & Natural History
[155]
Frangoul H, Altshuler D, Cappellini MD et al.. “CRISPR-Cas9 Gene Editing for Sickle Cell Disease and β-Thalassemia.” The New England journal of medicine (2020). PMID: 33283989 ↗
L4TRIAL_NONRANDOMCited in: 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)
[156]
Eapen M, Brazauskas R, Walters MC et al.. “Effect of donor type and conditioning regimen intensity on allogeneic transplantation outcomes in patients with sickle cell disease: a retrospective multicentre, cohort study.” The Lancet. Haematology (2019). PMID: 31495699 ↗
L3COHORTCited in: 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling, 9. Hematopoietic Cell Transplantation & Cellular Therapy, 12. Prognosis & Natural History
[157]
Sharma A, Locatelli F, Bhatia M et al.. “Improvements in health-related quality of life in patients with severe sickle cell disease after exagamglogene autotemcel.” Blood advances (2025). PMID: 40857358 ↗
L4TRIAL_NONRANDOMCited in: 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling, 8. Long-term & Definitive Management, 13. Special Populations & Pregnancy
[158]
Dhedin N, Bruno B, Paillard C et al.. “HLA-haploidentical hematopoietic stem cell transplantation in patients with sickle cell disease: results from the phase II DREP-HAPLO trial.” Haematologica (2025). PMID: 41376570 ↗
L4TRIAL_NONRANDOMCited in: 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling, 9. Hematopoietic Cell Transplantation & Cellular Therapy, 11. Complications, 12. Prognosis & Natural History, 13. Special Populations & Pregnancy
[159]
Lagresle-Peyrou C, Lefrère F, Magrin E et al.. “Plerixafor enables safe, rapid, efficient mobilization of hematopoietic stem cells in sickle cell disease patients after exchange transfusion.” Haematologica (2018). PMID: 29472357 ↗
L4TRIAL_NONRANDOMCited in: 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling, 9. Hematopoietic Cell Transplantation & Cellular Therapy, 11. Complications
[160]
Goyal S, Tisdale J, Schmidt M et al.. “Acute Myeloid Leukemia Case after Gene Therapy for Sickle Cell Disease.” The New England journal of medicine (2021). PMID: 34898140 ↗
L4CASE_REPORTCited in: 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling, 8. Long-term & Definitive Management
[161]
Khandros E, Blobel GA. “Elevating fetal hemoglobin: recently discovered regulators and mechanisms.” Blood (2024). PMID: 38728575 ↗
L5REVIEW_NARRATIVECited in: 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling, 8. Long-term & Definitive Management
[162]
Gordeuk VR, Castro OL, Machado RF. “Pathophysiology and treatment of pulmonary hypertension in sickle cell disease.” Blood (2016). PMID: 26758918 ↗
L5REVIEW_NARRATIVECited in: 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)
[163]
Joseph L, Driessen M. “A comprehensive view of pregnancy in patients with sickle cell disease in high-income countries: the need for robust data and further decline in morbidity and mortality.” The Lancet. Haematology (2024). PMID: 38135375 ↗
L5REVIEW_NARRATIVECited in: 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling, 8. Long-term & Definitive Management, 11. Complications, 13. Special Populations & Pregnancy
[164]
Nnodu OE, Sopekan A, Nnebe-Agumadu U et al.. “Implementing newborn screening for sickle cell disease as part of immunisation programmes in Nigeria: a feasibility study.” The Lancet. Haematology (2020). PMID: 32589979 ↗
L4OTHERCited in: 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling, 14. Prevention, Screening & Surveillance
[165]
DeBaun MR, Jordan LC, King AA et al.. “American Society of Hematology 2020 guidelines for sickle cell disease: prevention, diagnosis, and treatment of cerebrovascular disease in children and adults.” Blood advances (2020). PMID: 32298430 ↗
L1OTHERCited in: 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling, 8. Long-term & Definitive Management, 14. Prevention, Screening & Surveillance
[166]
Grunenwald A, Peliconi J, Lavergne J et al.. “Transcriptomic atlas reveals organ-specific disease tolerance in sickle cell mice.” Blood advances (2025). PMID: 39841947 ↗
L5OTHERCited in: 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling
[167]
Gendreau S, Coupry LM, Cappy P et al.. “Severe parvovirus B19 infection in patients with sickle cell disease hospitalized in intensive care units.” Blood advances (2025). PMID: 40526829 ↗
L3OTHERCited in: 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling, 11. Complications
[168]
Selma J, Song H, Rivera C et al.. “Sickle cell disease promotes sex-dependent pathological bone loss through enhanced cathepsin proteolytic activity in mice.” Blood advances (2022). PMID: 34547771 ↗
L5OTHERCited in: 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling
[169]
Olaniyan HS, Briscoe C, Muhongo M et al.. “Early diagnosis of sickle cell disease at birth hospitals and vaccination centers in Angola using point-of-care tests.” Blood advances (2023). PMID: 37399450 ↗
L4OTHERCited in: 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling
[170]
El Hoss S, Cochet S, Godard A et al.. “Fetal hemoglobin rescues ineffective erythropoiesis in sickle cell disease.” Haematologica (2021). PMID: 32855279 ↗
L5OTHERCited in: 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling
[171]
Ataga KI, Moore CG, Hillery CA et al.. “Coagulation activation and inflammation in sickle cell disease-associated pulmonary hypertension.” Haematologica (2008). PMID: 18166781 ↗
L4OTHERCited in: 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling
[172]
Lionnet F, Hammoudi N, Stojanovic KS et al.. “Hemoglobin sickle cell disease complications: a clinical study of 179 cases.” Haematologica (2012). PMID: 22315500 ↗
L4OTHERCited in: 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling
[173]
Venugopal J, Wang J, Mawri J et al.. “Interleukin-1 receptor inhibition reduces stroke size in a murine model of sickle cell disease.” Haematologica (2021). PMID: 32817286 ↗
L5OTHERCited in: 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling
[174]
McArthur JG, Svenstrup N, Chen C et al.. “A novel, highly potent and selective phosphodiesterase-9 inhibitor for the treatment of sickle cell disease.” Haematologica (2019). PMID: 31147439 ↗
L5OTHERCited in: 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling
[175]
Alkobtawi M, Sbeih M, Souaid K et al.. “Contribution of fetal microchimeric cells to maternal wound healing in sickle cell ulcers.” Haematologica (2023). PMID: 36373248 ↗
L5OTHERCited in: 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling, 11. Complications, 13. Special Populations & Pregnancy
[176]
Hebbel RP, Key NS. “Microparticles in sickle cell anaemia: promise and pitfalls.” British journal of haematology (2016). PMID: 27136195 ↗
L5REVIEW_NARRATIVECited in: 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling
[177]
Daniel Y, Henthorn J. “Lessons learnt in the screening and diagnosis of haemoglobinopathies.” British journal of haematology (2023). PMID: 37932940 ↗
L4REVIEW_NARRATIVECited in: 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling, 14. Prevention, Screening & Surveillance
[178]
Pinto FO, Roberts I. “Cord blood stem cell transplantation for haemoglobinopathies.” British journal of haematology (2008). PMID: 18307566 ↗
L5REVIEW_NARRATIVECited in: 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling, 8. Long-term & Definitive Management, 9. Hematopoietic Cell Transplantation & Cellular Therapy
[179]
Early ML, Raja M, Luo A et al.. “Blood pressure thresholds for the diagnosis of hypertensive disorders of pregnancy in sickle cell disease.” British journal of haematology (2023). PMID: 38093478 ↗
L2OTHERCited in: 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling, 13. Special Populations & Pregnancy
[180]
Chakravorty S, Dick MC. “Antenatal screening for haemoglobinopathies: current status, barriers and ethics.” British journal of haematology (2019). PMID: 31509241 ↗
L5REVIEW_NARRATIVECited in: 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling, 14. Prevention, Screening & Surveillance
[181]
Ibemere SO, Oyedeji CI, Preiss L et al.. “Characterising the prevalence of overweight and obese status among adults with sickle cell disease.” British journal of haematology (2022). PMID: 36382420 ↗
L2OTHERCited in: 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling
[182]
Setty BN, Betal SG, Zhang J et al.. “Heme induces endothelial tissue factor expression: potential role in hemostatic activation in patients with hemolytic anemia.” Journal of thrombosis and haemostasis : JTH (2008). PMID: 18983524 ↗
L5OTHERCited in: 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling
[183]
Martens MJ, Lian Q, Logan BR. “TITE-safety: a robust time-to-event safety monitoring approach for clinical trials.” Biometrics (2026). PMID: 42201841 ↗
L5TRIAL_NONRANDOMCited in: 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling, 8. Long-term & Definitive Management, 11. Complications
[184]
Alasbali R, Alzahrani M, Wilkerson K et al.. “Excellent outcomes using a novel reduced intensity conditioning with thiotepa and post-transplant cyclophosphamide for HLA-matched related donor transplant in adolescents and adults with sickle cell disease.” Bone marrow transplantation (2026). PMID: 42049986 ↗
L4TRIAL_NONRANDOMCited in: 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling, 9. Hematopoietic Cell Transplantation & Cellular Therapy, 11. Complications, 12. Prognosis & Natural History
[185]
Yee MEM, Zerra PE, Francis RO et al.. “Red blood cell transfusion survival in sickle cell disease is reduced by donor characteristics and recipient spleen activity.” Blood advances (2026). PMID: 42018645 ↗
L2TRIAL_NONRANDOMCited in: 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), 13. Special Populations & Pregnancy
[186]
Das S, Ghai G, Sathianath S et al.. “Systematic Review and Meta-analysis on the Prevalence of Common Hemoglobinopathies in India.” Annals of African medicine (2026). PMID: 41943545 ↗
L1SR_OBSCited in: 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling, 14. Prevention, Screening & Surveillance
[187]
Adelabu Y, Fakile UO, Oladimeji WQ et al.. “Bladder mass following bone marrow transplant for sickle cell disease: A diagnostic dilemma.” Clinical hematology international (2026). PMID: 42099830 ↗
L4CASE_REPORTCited in: 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling, 9. Hematopoietic Cell Transplantation & Cellular Therapy
[188]
Lembeck AL, Wölfler A, Zebisch A et al.. “Fish-shaped erythrocytes and pincer cells co-occur in distinct hematological disorders and are associated with anemia severity.” Clinical chemistry and laboratory medicine (2026). PMID: 42406051 ↗
L4OTHERCited in: 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling
[189]
Wasilwa MO, Simiyu V, Onduru F et al.. “Infectious pathogens associated with stillbirth and under-five mortality by sickle cell disease in Western Kenya: a cross-sectional study.” BMC infectious diseases (2026). PMID: 42380786 ↗
L2OTHERCited in: 5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling
[190]
Farrell AT, Panepinto J, Carroll CP et al.. “End points for sickle cell disease clinical trials: patient-reported outcomes, pain, and the brain.” Blood advances (2019). PMID: 31809538 ↗
L1TRIAL_NONRANDOMCited in: 6. Staging, Risk Stratification & Prognostic Scoring
[191]
Al Balushi HWM, Wali Y, Al Awadi M et al.. “The super sickling haemoglobin HbS-Oman: a study of red cell sickling, K+ permeability and associations with disease severity in patients heterozygous for HbA and HbS-Oman (HbA/S-Oman genotype).” British journal of haematology (2017). PMID: 28699687 ↗
L3TRIAL_NONRANDOMCited in: 6. Staging, Risk Stratification & Prognostic Scoring
[192]
Kim MG, Yu K, Yeh CY et al.. “Low-intensity transcranial focused ultrasound suppresses pain by modulating pain-processing brain circuits.” Blood (2024). PMID: 38976875 ↗
L5OTHERCited in: 6. Staging, Risk Stratification & Prognostic Scoring, 8. Long-term & Definitive Management
[193]
Brazauskas R, Scigliuolo GM, Wang HL et al.. “Risk score to predict event-free survival after hematopoietic cell transplant for sickle cell disease.” Blood (2020). PMID: 32518950 ↗
L2OTHERCited in: 6. Staging, Risk Stratification & Prognostic Scoring
[194]
Chen Q, Hazra R, Crosby D et al.. “Heme-induced loss of renovascular endothelial protein C receptor promotes chronic kidney disease in sickle mice.” Blood (2024). PMID: 38820589 ↗
L5OTHERCited in: 6. Staging, Risk Stratification & Prognostic Scoring
[195]
Escobar Alvarez SN, Myers ER. “Impact of a grant program to spur advances in sickle cell disease research.” Blood advances (2021). PMID: 34570224 ↗
L5OTHERCited in: 6. Staging, Risk Stratification & Prognostic Scoring
[196]
Chang TC, Yu J, Wang Z et al.. “Machine learning to optimize automated RH genotyping using whole-exome sequencing data.” Blood advances (2024). PMID: 38522094 ↗
L4OTHERCited in: 6. Staging, Risk Stratification & Prognostic Scoring
[197]
McCuskee S, Liu Z, Lee HC et al.. “Retinal imaging and supervised learning predict hospitalizations and kidney and heart-lung damage in sickle cell disease.” Blood advances (2026). PMID: 42059643 ↗
L2OTHERCited in: 6. Staging, Risk Stratification & Prognostic Scoring
[198]
Chang TC, Haupfear KM, Yu J et al.. “A novel algorithm comprehensively characterizes human RH genes using whole-genome sequencing data.” Blood advances (2020). PMID: 32915977 ↗
L4OTHERCited in: 6. Staging, Risk Stratification & Prognostic Scoring
[199]
Ladisa F, Morelli E, Soncini D et al.. “CRISPR application in hematological disorders: from bench to bedside.” Blood advances (2026). PMID: 42263664 ↗
L5OTHERCited in: 6. Staging, Risk Stratification & Prognostic Scoring
[200]
Allali S, Taylor M, Brice J et al.. “Chronic organ injuries in children with sickle cell disease.” Haematologica (2021). PMID: 33626864 ↗
L5OTHERCited in: 6. Staging, Risk Stratification & Prognostic Scoring, 8. Long-term & Definitive Management, 14. Prevention, Screening & Surveillance
[201]
Ray R, Li H, Gao S et al.. “Variations in mitochondrial genome as potential prognostic markers in sickle cell disease.” Haematologica (2026). PMID: 41852318 ↗
L4OTHERCited in: 6. Staging, Risk Stratification & Prognostic Scoring
[202]
Voskaridou E, Tsetsos G, Tsoutsias A et al.. “Pulmonary hypertension in patients with sickle cell/beta thalassemia: incidence and correlation with serum N-terminal pro-brain natriuretic peptide concentrations.” Haematologica (2007). PMID: 17550845 ↗
L4OTHERCited in: 6. Staging, Risk Stratification & Prognostic Scoring
[203]
Ataga KI, Stocker J. “The trials and hopes for drug development in sickle cell disease.” British journal of haematology (2015). PMID: 26123612 ↗
L5REVIEW_NARRATIVECited in: 6. Staging, Risk Stratification & Prognostic Scoring, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)
[204]
Brewin J, Kaya B, Chakravorty S. “How I manage sickle cell patients with high transcranial doppler results.” British journal of haematology (2017). PMID: 28771666 ↗
L5REVIEW_NARRATIVECited in: 6. Staging, Risk Stratification & Prognostic Scoring
[205]
Sachdev V, Tian X, Gu Y et al.. “A phenotypic risk score for predicting mortality in sickle cell disease.” British journal of haematology (2021). PMID: 33506990 ↗
L2OTHERCited in: 6. Staging, Risk Stratification & Prognostic Scoring
[206]
Václavů L, Baldew ZAV, Gevers S et al.. “Intracranial 4D flow magnetic resonance imaging reveals altered haemodynamics in sickle cell disease.” British journal of haematology (2017). PMID: 29270975 ↗
L3OTHERCited in: 6. Staging, Risk Stratification & Prognostic Scoring
[207]
Dexter D, McGann PT. “Saving lives through early diagnosis: the promise and role of point of care testing for sickle cell disease.” British journal of haematology (2021). PMID: 34340260 ↗
L5OTHERCited in: 6. Staging, Risk Stratification & Prognostic Scoring
[208]
Hines PC, Callaghan MU, Zaidi AU et al.. “Flow adhesion of whole blood to P-selectin: a prognostic biomarker for vaso-occlusive crisis in sickle cell disease.” British journal of haematology (2021). PMID: 34472086 ↗
L2OTHERCited in: 6. Staging, Risk Stratification & Prognostic Scoring
[209]
Ali NT, Abdullah RS, Mehdi MAH et al.. “AI-Augmented Hematological Signatures for Equitable Detection of Hereditary Hemolytic Anemia Carriers: A Global Systematic Review and Meta-Analysis.” Human mutation (2026). PMID: 42369207 ↗
L1SR_OBSCited in: 6. Staging, Risk Stratification & Prognostic Scoring, 14. Prevention, Screening & Surveillance
[210]
Bills SE, Schatz J, Gillooly E et al.. “Academic and cerebrovascular outcomes after neurodevelopmental screening in sickle cell disease: A longitudinal cohort study.” Developmental medicine and child neurology (2025). PMID: 41235698 ↗
L2COHORTCited in: 6. Staging, Risk Stratification & Prognostic Scoring
[211]
Alamin AA, Yahia AIO, Ibrahim E et al.. “Platelet-Red Blood Cell Interactions in Thrombosis: Integrating Hemodynamic, Molecular, and Clinical Evidence-A Systematic Review.” Seminars in thrombosis and hemostasis (2026). PMID: 42190738 ↗
L2SR_OBSCited in: 6. Staging, Risk Stratification & Prognostic Scoring, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), 12. Prognosis & Natural History
[212]
Almarshad HA. “Blood viscosity in clinical practice: A critical review of diagnostic utility, therapeutic implications, and evidence gaps.” Clinical hemorheology and microcirculation (2026). PMID: 42089664 ↗
L5SR_OBSCited in: 6. Staging, Risk Stratification & Prognostic Scoring
[213]
Resta C, Xiong R, Sturrock S et al.. “Non-invasive prenatal testing for the diagnosis of sickle cell disease in high-risk pregnancies: A systematic review and statistical summary of the current literature.” European journal of obstetrics, gynecology, and reproductive biology (2025). PMID: 41192133 ↗
L2SR_OBSCited in: 6. Staging, Risk Stratification & Prognostic Scoring
[214]
Alwaheed AJ, Alqatari SG, Alalwan SJ et al.. “The Role of Platelet-to-Neutrophil Ratio as a Biomarker for Pulmonary Hypertension in Sickle Cell Disease Patients: A Retrospective Cohort Study.” Medicina (Kaunas, Lithuania) (2026). PMID: 42075644 ↗
L3COHORTCited in: 6. Staging, Risk Stratification & Prognostic Scoring, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)
[215]
Belisário AR, Ozahata MC, Moura ICG et al.. “Laboratory and genetic characteristic associated with gallbladder-related outcomes in sickle cell disease in Brazil: results from the REDS-III multicenter cohort study.” Annals of hematology (2026). PMID: 41692868 ↗
L2COHORTCited in: 6. Staging, Risk Stratification & Prognostic Scoring
[216]
Morris CR, Brown LAS, Reynolds M et al.. “Impact of arginine therapy on mitochondrial function in children with sickle cell disease during vaso-occlusive pain.” Blood (2020). PMID: 32384147 ↗
L1RCTCited in: 7. Acute & Emergency Management
[217]
Bain BJ, Daniel Y, Henthorn J et al.. “Significant haemoglobinopathies: A guideline for screening and diagnosis: A British Society for Haematology Guideline: A British Society for Haematology Guideline.” British journal of haematology (2023). PMID: 37271570 ↗
L1GUIDELINECited in: 7. Acute & Emergency Management
[218]
Morris CR, Kuypers FA, Lavrisha L et al.. “A randomized, placebo-controlled trial of arginine therapy for the treatment of children with sickle cell disease hospitalized with vaso-occlusive pain episodes.” Haematologica (2013). PMID: 23645695 ↗
L1RCTCited in: 7. Acute & Emergency Management, History and Evolution of Treatment
[219]
Siewny L, King A, Melvin CL et al.. “Impact of an individualized pain plan to treat sickle cell disease vaso-occlusive episodes in the emergency department.” Blood advances (2024). PMID: 38815230 ↗
L2TRIAL_NONRANDOMCited in: 7. Acute & Emergency Management
[220]
Lobo CL, Pinto JF, Nascimento EM et al.. “The effect of hydroxcarbamide therapy on survival of children with sickle cell disease.” British journal of haematology (2013). PMID: 23590693 ↗
L3TRIAL_NONRANDOMCited in: 7. Acute & Emergency Management
[221]
Karkoska K, Appiah-Kubi A, Rocker J et al.. “Management of vaso-occlusive episodes in the day hospital decreases admissions in children with sickle cell disease.” British journal of haematology (2019). PMID: 31148158 ↗
L3TRIAL_NONRANDOMCited in: 7. Acute & Emergency Management
[222]
Rech JS, Cohen A, Bartolucci P et al.. “Shift in emergency department utilization by frequent attendees with sickle cell disease during the COVID-19 pandemic: A multicentre cohort study.” British journal of haematology (2024). PMID: 38960400 ↗
L2COHORTCited in: 7. Acute & Emergency Management
[223]
Zhou J, Han J, Nutescu EA et al.. “Hydroxycarbamide adherence and cumulative dose associated with hospital readmission in sickle cell disease: a 6-year population-based cohort study.” British journal of haematology (2018). PMID: 29767446 ↗
L3COHORTCited in: 7. Acute & Emergency Management
[224]
Ballas SK, Gupta K, Adams-Graves P. “Sickle cell pain: a critical reappraisal.” Blood (2012). PMID: 22923496 ↗
L5REVIEW_NARRATIVECited in: 7. Acute & Emergency Management
[225]
Hillery CA, Kerstein PC, Vilceanu D et al.. “Transient receptor potential vanilloid 1 mediates pain in mice with severe sickle cell disease.” Blood (2011). PMID: 21708890 ↗
L5OTHERCited in: 7. Acute & Emergency Management
[226]
Hariharan N, Brunson A, Mahajan A et al.. “Bleeding in patients with sickle cell disease: a population-based study.” Blood advances (2020). PMID: 32108229 ↗
L2OTHERCited in: 7. Acute & Emergency Management
[227]
Howell KE, Kayle M, Smeltzer MP et al.. “Gaps during pediatric to adult care transfer escalate acute resource utilization in sickle cell disease.” Blood advances (2024). PMID: 38809136 ↗
L2OTHERCited in: 7. Acute & Emergency Management
[228]
Wesevich A, Woelkers M, Adegunsoye A et al.. “Triaging acute chest syndrome clinical decision-making using bedside SaO2/FiO2 ratio.” Blood advances (2025). PMID: 40179390 ↗
L2OTHERCited in: 7. Acute & Emergency Management
[229]
MacEwan SR, Chiang C, O'Brien SH et al.. “Comparing super-utilizers and lower-utilizers among commercial- and Medicare-insured adults with sickle cell disease.” Blood advances (2024). PMID: 37991988 ↗
L2OTHERCited in: 7. Acute & Emergency Management
[230]
Khan H, Kang G, Porter JS et al.. “Social determinants of health affect disease severity among preschool children with sickle cell disease.” Blood advances (2024). PMID: 39373640 ↗
L2OTHERCited in: 7. Acute & Emergency Management
[231]
Coisy F, Simon A, Occelli C et al.. “Does a history of sickle cell disease affect the prescription of morphine? An international, randomised study based on clinical vignettes conducted among emergency physicians.” BMJ open (2025). PMID: 41448706 ↗
L2RCTCited in: 7. Acute & Emergency Management
[232]
Adewoye AH, Nolan V, McMahon L et al.. “Effectiveness of a dedicated day hospital for management of acute sickle cell pain.” Haematologica (2007). PMID: 17550862 ↗
L4OTHERCited in: 7. Acute & Emergency Management
[233]
Telfer P, Bahal N, Lo A et al.. “Management of the acute painful crisis in sickle cell disease- a re-evaluation of the use of opioids in adult patients.” British journal of haematology (2014). PMID: 24750050 ↗
L5REVIEW_NARRATIVECited in: 7. Acute & Emergency Management
[234]
Khalid A, Riaño AS, Mohnkern JD et al.. “Early vs delayed opioid administration for pediatric sickle cell vaso-occlusive crisis: A systematic review and meta-analysis.” The American journal of emergency medicine (2026). PMID: 42190636 ↗
L1SR_OBSCited in: 7. Acute & Emergency Management, 13. Special Populations & Pregnancy
[235]
Amenah DB, Afaya A, Klinogo F et al.. “Sociocultural and health system determinants of maternal mortality in Ghana: findings from a systematic review.” BMC public health (2026). PMID: 41794701 ↗
L1SR_OBSCited in: 7. Acute & Emergency Management
[236]
Rice CT, Besser M, Baker CL et al.. “Empirical estimate for the indirect healthcare costs of sickle cell disease from a retrospective cohort study in England between 2007 and 2019.” BMC health services research (2026). PMID: 42243888 ↗
L2COHORTCited in: 7. Acute & Emergency Management
[237]
Owusu-Antwi P, Muhialdain M, Atodaria P et al.. “Risperidone-Induced Priapism: A Systematic Review of Risk Factors, Comprehensive Assessment, and Management Recommendations.” Journal of clinical psychopharmacology (2026). PMID: 41930469 ↗
L1SR_OBSCited in: 7. Acute & Emergency Management
[238]
Belton TD, Steinway CM, Teng O et al.. “The Community Health Workers and Mobile Health for Emerging Adults Transitioning Sickle Cell Disease Care (COMETS) Trial: Protocol for a Randomized Controlled Trial.” JMIR research protocols (2025). PMID: 40905609 ↗
L5TRIAL_NONRANDOMCited in: 7. Acute & Emergency Management
[239]
Chou ST, Alsawas M, Fasano RM et al.. “American Society of Hematology 2020 guidelines for sickle cell disease: transfusion support.” Blood advances (2020). PMID: 31985807 ↗
L1GUIDELINECited in: 8. Long-term & Definitive Management, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), History and Evolution of Treatment, 13. Special Populations & Pregnancy, 14. Prevention, Screening & Surveillance
[240]
Kanter J, Liem RI, Bernaudin F et al.. “American Society of Hematology 2021 guidelines for sickle cell disease: stem cell transplantation.” Blood advances (2021). PMID: 34581773 ↗
L1GUIDELINECited in: 8. Long-term & Definitive Management, 9. Hematopoietic Cell Transplantation & Cellular Therapy, History and Evolution of Treatment
[241]
Angelucci E, Matthes-Martin S, Baronciani D et al.. “Hematopoietic stem cell transplantation in thalassemia major and sickle cell disease: indications and management recommendations from an international expert panel.” Haematologica (2014). PMID: 24790059 ↗
L1GUIDELINECited in: 8. Long-term & Definitive Management, 9. Hematopoietic Cell Transplantation & Cellular Therapy, History and Evolution of Treatment, 12. Prognosis & Natural History, 14. Prevention, Screening & Surveillance
[242]
Saraf SL, Hagar R, Idowu M et al.. “Multicenter, phase 1 study of etavopivat (FT-4202) treatment for up to 12 weeks in patients with sickle cell disease.” Blood advances (2024). PMID: 38640200 ↗
L1RCTCited in: 8. Long-term & Definitive Management, History and Evolution of Treatment
[243]
Frangoul H, Locatelli F, Sharma A et al.. “Exagamglogene Autotemcel for Severe Sickle Cell Disease.” The New England journal of medicine (2024). PMID: 38661449 ↗
L2TRIAL_NONRANDOMCited in: 8. Long-term & Definitive Management, 9. Hematopoietic Cell Transplantation & Cellular Therapy, 14. Prevention, Screening & Surveillance
[244]
Kanter J, Walters MC, Krishnamurti L et al.. “Biologic and Clinical Efficacy of LentiGlobin for Sickle Cell Disease.” The New England journal of medicine (2021). PMID: 34898139 ↗
L2TRIAL_NONRANDOMCited in: 8. Long-term & Definitive Management, History and Evolution of Treatment
[245]
Esrick EB, Lehmann LE, Biffi A et al.. “Post-Transcriptional Genetic Silencing of BCL11A to Treat Sickle Cell Disease.” The New England journal of medicine (2020). PMID: 33283990 ↗
L2TRIAL_NONRANDOMCited in: 8. Long-term & Definitive Management
[246]
Gupta AO, Sharma A, Frangoul H et al.. “Base Editing of HBG1 and HBG2 Promoters for Sickle Cell Disease.” The New England journal of medicine (2026). PMID: 41931046 ↗
L2TRIAL_NONRANDOMCited in: 8. Long-term & Definitive Management, 9. Hematopoietic Cell Transplantation & Cellular Therapy, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)
[247]
Hanna R, Frangoul H, Pineiro L et al.. “CRISPR-Cas12a Gene Editing of HBG1 and HBG2 Promoters to Treat Sickle Cell Disease.” The New England journal of medicine (2026). PMID: 41931047 ↗
L2TRIAL_NONRANDOMCited in: 8. Long-term & Definitive Management, 9. Hematopoietic Cell Transplantation & Cellular Therapy, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)
[248]
Hsieh MM, Kang EM, Fitzhugh CD et al.. “Allogeneic hematopoietic stem-cell transplantation for sickle cell disease.” The New England journal of medicine (2009). PMID: 20007560 ↗
L4TRIAL_NONRANDOMCited in: 8. Long-term & Definitive Management, 9. Hematopoietic Cell Transplantation & Cellular Therapy
[249]
van Dijk MJ, Rab MAE, van Oirschot BA et al.. “One-year safety and efficacy of mitapivat in sickle cell disease: follow-up results of a phase 2, open-label study.” Blood advances (2023). PMID: 37934880 ↗
L2TRIAL_NONRANDOMCited in: 8. Long-term & Definitive Management, 11. Complications
[250]
Le K, Wang X, Chu J et al.. “Activating pyruvate kinase improves red blood cell integrity by reducing band 3 tyrosine phosphorylation.” Blood advances (2024). PMID: 39265169 ↗
L2TRIAL_NONRANDOMCited in: 8. Long-term & Definitive Management, 12. Prognosis & Natural History
[251]
D'Alessandro A, Le K, Lundt M et al.. “Functional and multi-omics signatures of mitapivat efficacy upon activation of pyruvate kinase in red blood cells from patients with sickle cell disease.” Haematologica (2024). PMID: 38450513 ↗
L4TRIAL_NONRANDOMCited in: 8. Long-term & Definitive Management
[252]
Lopinto J, Gendreau S, Berti E et al.. “Effects of corticosteroids in patients with sickle cell disease and acute complications: a systematic review and meta-analysis.” Haematologica (2022). PMID: 35021607 ↗
L1SR_OBSCited in: 8. Long-term & Definitive Management, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), 12. Prognosis & Natural History
[253]
Sharma A. “How I treat sickle cell disease with gene therapy.” Blood (2024). PMID: 39356871 ↗
L5OTHERCited in: 8. Long-term & Definitive Management, History and Evolution of Treatment, 11. Complications, 14. Prevention, Screening & Surveillance
[254]
Gallagher PG. “Disorders of erythrocyte hydration.” Blood (2017). PMID: 29051181 ↗
L5REVIEW_NARRATIVECited in: 8. Long-term & Definitive Management, 14. Prevention, Screening & Surveillance
[255]
Wang Y, Yu L, Deng K et al.. “Novel, potent, and orally bioavailable LSD1 inhibitors induce fetal hemoglobin synthesis in a sickle cell disease mouse model.” Blood (2025). PMID: 40332031 ↗
L5OTHERCited in: 8. Long-term & Definitive Management
[256]
Vats R, Kaminski TW, Brzoska T et al.. “Liver-to-lung microembolic NETs promote gasdermin D-dependent inflammatory lung injury in sickle cell disease.” Blood (2022). PMID: 35737916 ↗
L5OTHERCited in: 8. Long-term & Definitive Management, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)
[257]
Nguyen KA, Matte A, Foresti R et al.. “An oral carbon monoxide-releasing molecule protects against acute hyperhemolysis in sickle cell disease.” Blood (2024). PMID: 38518106 ↗
L5OTHERCited in: 8. Long-term & Definitive Management, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), History and Evolution of Treatment, 11. Complications
[258]
Drown L, Osei M, Thapa A et al.. “Models of care for sickle cell disease in low-income and lower-middle-income countries: a scoping review.” The Lancet. Haematology (2024). PMID: 38432241 ↗
L5REVIEW_NARRATIVECited in: 8. Long-term & Definitive Management
[259]
Pecker LH, Oteng-Ntim E, Nero A et al.. “Expecting more: the case for incorporating fertility services into comprehensive sickle cell disease care.” The Lancet. Haematology (2023). PMID: 36708736 ↗
L5REVIEW_NARRATIVECited in: 8. Long-term & Definitive Management, History and Evolution of Treatment, 13. Special Populations & Pregnancy, 14. Prevention, Screening & Surveillance
[260]
Pirenne F, Floch A, Diop S. “Alloimmunisation against red blood cells in sickle cell disease: transfusion challenges in high-income and low-income countries.” The Lancet. Haematology (2023). PMID: 37060916 ↗
L5REVIEW_NARRATIVECited in: 8. Long-term & Definitive Management, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), 14. Prevention, Screening & Surveillance
[261]
de la Fuente J, Gluckman E, Makani J et al.. “The role of haematopoietic stem cell transplantation for sickle cell disease in the era of targeted disease-modifying therapies and gene editing.” The Lancet. Haematology (2020). PMID: 33242447 ↗
L5REVIEW_NARRATIVECited in: 8. Long-term & Definitive Management
[262]
Frangoul H, de la Fuente J, Chopra Y et al.. “Exa-cel in Children with Transfusion-Dependent β-Thalassemia or Sickle Cell Disease.” The New England journal of medicine (2026). PMID: 42274009 ↗
L4OTHERCited in: 8. Long-term & Definitive Management, 9. Hematopoietic Cell Transplantation & Cellular Therapy, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)
[263]
Brandow AM, Carroll CP, Creary S et al.. “American Society of Hematology 2020 guidelines for sickle cell disease: management of acute and chronic pain.” Blood advances (2020). PMID: 32559294 ↗
L1OTHERCited in: 8. Long-term & Definitive Management
[264]
Lanzkron S, Manwani D, Desai P et al.. “GRNDaD: big data and sickle cell disease.” Blood advances (2022). PMID: 35133406 ↗
L5OTHERCited in: 8. Long-term & Definitive Management, History and Evolution of Treatment
[265]
Taher AT, Weatherall DJ, Cappellini MD. “Thalassaemia.” Lancet (London, England) (2017). PMID: 28774421 ↗
L5REVIEW_NARRATIVECited in: 8. Long-term & Definitive Management, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)
[266]
Higgs DR, Engel JD, Stamatoyannopoulos G. “Thalassaemia.” Lancet (London, England) (2011). PMID: 21908035 ↗
L5REVIEW_NARRATIVECited in: 8. Long-term & Definitive Management, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)
[267]
Doeven T, Glenthøj A, Grace RF et al.. “Pyruvate kinase activators in hereditary haemolytic anaemias: current evidence and clinical potential.” Lancet (London, England) (2026). PMID: 41833294 ↗
L5REVIEW_NARRATIVECited in: 8. Long-term & Definitive Management
[268]
Oakley LL, McDermott C, Robinson V et al.. “The acceptability and feasibility of a randomised controlled trial of serial prophylactic exchange blood transfusion versus usual care in pregnant women with sickle cell disease: a qualitative study.” BMC pregnancy and childbirth (2026). PMID: 42399799 ↗
L5RCTCited in: 8. Long-term & Definitive Management, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), 11. Complications, 12. Prognosis & Natural History, 13. Special Populations & Pregnancy
[269]
Linder GE, Chou ST. “Red cell transfusion and alloimmunization in sickle cell disease.” Haematologica (2021). PMID: 33792218 ↗
L5REVIEW_NARRATIVECited in: 8. Long-term & Definitive Management, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), 14. Prevention, Screening & Surveillance
[270]
Geisness AC, Azul M, Williams D et al.. “Ionophore-mediated swelling of erythrocytes as a therapeutic mechanism in sickle cell disease.” Haematologica (2022). PMID: 34706495 ↗
L5OTHERCited in: 8. Long-term & Definitive Management, 11. Complications, 14. Prevention, Screening & Surveillance
[271]
Saraf SL, Zhang X, Shah B et al.. “Genetic variants and cell-free hemoglobin processing in sickle cell nephropathy.” Haematologica (2015). PMID: 26206798 ↗
L2OTHERCited in: 8. Long-term & Definitive Management
[272]
Khasabova IA, Gable J, Johns M et al.. “Inhibition of DAGLβ as a therapeutic target for pain in sickle cell disease.” Haematologica (2023). PMID: 35615929 ↗
L5OTHERCited in: 8. Long-term & Definitive Management
[273]
Rossato P, Federti E, Matte A et al.. “Evidence of protective effects of recombinant ADAMTS13 in a humanized model of sickle cell disease.” Haematologica (2022). PMID: 35443560 ↗
L5OTHERCited in: 8. Long-term & Definitive Management
[274]
Nardo-Marino A, Brousse V, Rees D. “Emerging therapies in sickle cell disease.” British journal of haematology (2020). PMID: 32142156 ↗
L5REVIEW_NARRATIVECited in: 8. Long-term & Definitive Management
[275]
Sobota A, Sabharwal V, Fonebi G et al.. “How we prevent and manage infection in sickle cell disease.” British journal of haematology (2015). PMID: 26018640 ↗
L5REVIEW_NARRATIVECited in: 8. Long-term & Definitive Management, 11. Complications, 12. Prognosis & Natural History, 14. Prevention, Screening & Surveillance
[276]
Lucania G, Vitrano A, Filosa A et al.. “Chelation treatment in sickle-cell-anaemia: much ado about nothing?” British journal of haematology (2011). PMID: 21707578 ↗
L5REVIEW_NARRATIVECited in: 8. Long-term & Definitive Management
[277]
Shandley LM, Fasano RM, Spencer JB et al.. “The impact of sickle cell disease and its treatment on ovarian reserve in reproductive-aged Black women.” British journal of haematology (2024). PMID: 38841818 ↗
L4OTHERCited in: 8. Long-term & Definitive Management
[278]
Mishkin AD, Prince EJ, Leimbach EJ et al.. “Psychiatric comorbidities in adults with sickle cell disease: A narrative review.” British journal of haematology (2023). PMID: 37455514 ↗
L5REVIEW_NARRATIVECited in: 8. Long-term & Definitive Management
[279]
Voskaridou E, Christoulas D, Terpos E. “Sickle-cell disease and the heart: review of the current literature.” British journal of haematology (2012). PMID: 22530942 ↗
L5REVIEW_NARRATIVECited in: 8. Long-term & Definitive Management, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), 12. Prognosis & Natural History
[280]
Segbefia C, Luchtman-Jones L. “Seeing haemoglobin SC: Challenging the misperceptions.” British journal of haematology (2024). PMID: 38922871 ↗
L5OTHERCited in: 8. Long-term & Definitive Management
[281]
Hunt RC, Katneni U, Yalamanoglu A et al.. “Contribution of ADAMTS13-independent VWF regulation in sickle cell disease.” Journal of thrombosis and haemostasis : JTH (2022). PMID: 35753044 ↗
L4OTHERCited in: 8. Long-term & Definitive Management, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)
[282]
Stivala S, Gobbato S, Bonetti N et al.. “Dietary alpha-linolenic acid reduces platelet activation and collagen-mediated cell adhesion in sickle cell disease mice.” Journal of thrombosis and haemostasis : JTH (2021). PMID: 34758193 ↗
L5OTHERCited in: 8. Long-term & Definitive Management, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), 12. Prognosis & Natural History
[283]
Rossato P, Glantschnig H, Canneva F et al.. “Treatment with recombinant ADAMTS13, alleviates hypoxia/reoxygenation-induced pathologies in a mouse model of human sickle cell disease.” Journal of thrombosis and haemostasis : JTH (2022). PMID: 36700507 ↗
L5OTHERCited in: 8. Long-term & Definitive Management
[284]
Annarapu GK, Nolfi-Donegan D, Reynolds M et al.. “Mitochondrial reactive oxygen species scavenging attenuates thrombus formation in a murine model of sickle cell disease.” Journal of thrombosis and haemostasis : JTH (2021). PMID: 33724688 ↗
L5OTHERCited in: 8. Long-term & Definitive Management, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), 12. Prognosis & Natural History
[285]
Wang J, Silaghi P, Eitzman DT. “Sickle hemoglobin promotes venous thrombosis through procoagulant activity and is targetable by hemoglobinase therapy.” Journal of thrombosis and haemostasis : JTH (2026). PMID: 41941897 ↗
L5OTHERCited in: 8. Long-term & Definitive Management
[286]
Shaik MY, Divers S. “Efficacy, Safety, and Treatment-Delivery Feasibility of Autologous Gene Therapy for Sickle Cell Disease: A Systematic Review With Descriptive Synthesis of Clinical Trials.” European journal of haematology (2026). PMID: 42400217 ↗
L4TRIAL_NONRANDOMCited in: 8. Long-term & Definitive Management, 9. Hematopoietic Cell Transplantation & Cellular Therapy, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), History and Evolution of Treatment, 12. Prognosis & Natural History, 14. Prevention, Screening & Surveillance
[287]
Andemariam B, Wufsus A, Hecht E et al.. “Motivators and Barriers Affecting Decisions to Participate in Clinical Trials for Sickle Cell Disease: United States Findings from the Quantitative LISTEN Survey.” Journal of racial and ethnic health disparities (2026). PMID: 42323491 ↗
L4TRIAL_NONRANDOMCited in: 8. Long-term & Definitive Management
[288]
Zimmerman EI, Callegari E, Sharma R et al.. “A Phase 1 Microtracer Study Evaluating the Mass Balance, Excretion, and Pharmacokinetics of Osivelotor in Healthy Participants.” Clinical and translational science (2026). PMID: 42183775 ↗
L4TRIAL_NONRANDOMCited in: 8. Long-term & Definitive Management
[289]
Zhou X, Ma T, Ding X et al.. “The evolving landscape of gene editing therapies for human genetic diseases: a twenty-year bibliometric analysis.” Frontiers in medicine (2026). PMID: 42318429 ↗
L5SR_OBSCited in: 8. Long-term & Definitive Management, History and Evolution of Treatment
[290]
Alsalman M, Alnajjar JS, Alhassan SR et al.. “Global Prevalence of Alloimmunization in Adults with Sickle Cell Disease Receiving Red Blood Cell Transfusions: A Systematic Review and Meta-Analysis.” Journal of clinical medicine (2026). PMID: 42194795 ↗
L2SR_OBSCited in: 8. Long-term & Definitive Management, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), 11. Complications
[291]
Sharma A, Corbacioglu S. “Alternative Conditioning Regimens for Hemoglobinopathy Gene Therapy: Balancing Efficacy, Toxicity, and the Next Frontier.” Blood advances (2026). PMID: 42418372 ↗
L5OTHERCited in: 8. Long-term & Definitive Management, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)
[292]
van der Veen S, Biemond BJ, Cnossen MH et al.. “Undetectable Hydroxyurea Levels in the Majority of Sickle Cell Disease Patients, Especially in Young Children.” American journal of hematology (2026). PMID: 42400197 ↗
L4OTHERCited in: 8. Long-term & Definitive Management, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)
[293]
Bolaños-Meade J, Fuchs EJ, Luznik L et al.. “HLA-haploidentical bone marrow transplantation with posttransplant cyclophosphamide expands the donor pool for patients with sickle cell disease.” Blood (2012). PMID: 22955919 ↗
L4TRIAL_NONRANDOMCited in: 9. Hematopoietic Cell Transplantation & Cellular Therapy
[294]
Sharma A, Boelens JJ, Cancio M et al.. “CRISPR-Cas9 Editing of the HBG1 and HBG2 Promoters to Treat Sickle Cell Disease.” The New England journal of medicine (2023). PMID: 37646679 ↗
L4TRIAL_NONRANDOMCited in: 9. Hematopoietic Cell Transplantation & Cellular Therapy, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), 11. Complications
[295]
Nickel RS, Abraham A, Chiang KY et al.. “Nonmyeloablative HLA-identical sibling transplant for sickle cell disease in children: a multicenter prospective study.” Blood advances (2026). PMID: 41945757 ↗
L4TRIAL_NONRANDOMCited in: 9. Hematopoietic Cell Transplantation & Cellular Therapy, 11. Complications
[296]
Alzahrani M, Damlaj M, Jeffries N et al.. “Non-myeloablative human leukocyte antigen-matched related donor transplantation in sickle cell disease: outcomes from three independent centres.” British journal of haematology (2021). PMID: 33534948 ↗
L4TRIAL_NONRANDOMCited in: 9. Hematopoietic Cell Transplantation & Cellular Therapy
[297]
Nickel RS, Horan JT, Abraham A et al.. “Human leukocyte antigen (HLA) class I antibodies and transfusion support in paediatric HLA-matched haematopoietic cell transplant for sickle cell disease.” British journal of haematology (2019). PMID: 31674662 ↗
L2TRIAL_NONRANDOMCited in: 9. Hematopoietic Cell Transplantation & Cellular Therapy
[298]
Kassim AA, Galadanci NA, Pruthi S et al.. “How I treat and manage strokes in sickle cell disease.” Blood (2015). PMID: 25824688 ↗
L5CASE_REPORTCited in: 9. Hematopoietic Cell Transplantation & Cellular Therapy, 14. Prevention, Screening & Surveillance
[299]
Magrin E, Miccio A, Cavazzana M. “Lentiviral and genome-editing strategies for the treatment of β-hemoglobinopathies.” Blood (2019). PMID: 31467062 ↗
L5REVIEW_NARRATIVECited in: 9. Hematopoietic Cell Transplantation & Cellular Therapy, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)
[300]
Abraham AA, Tisdale JF. “Gene therapy for sickle cell disease: moving from the bench to the bedside.” Blood (2021). PMID: 34232993 ↗
L5REVIEW_NARRATIVECited in: 9. Hematopoietic Cell Transplantation & Cellular Therapy, 14. Prevention, Screening & Surveillance
[301]
Hsieh MM, Fitzhugh CD, Tisdale JF. “Allogeneic hematopoietic stem cell transplantation for sickle cell disease: the time is now.” Blood (2011). PMID: 21628400 ↗
L5REVIEW_NARRATIVECited in: 9. Hematopoietic Cell Transplantation & Cellular Therapy, 11. Complications
[302]
Gluckman E, Cappelli B, Bernaudin F et al.. “Sickle cell disease: an international survey of results of HLA-identical sibling hematopoietic stem cell transplantation.” Blood (2016). PMID: 27965196 ↗
L2OTHERCited in: 9. Hematopoietic Cell Transplantation & Cellular Therapy
[303]
Arumugam PI, Mullins ES, Shanmukhappa SK et al.. “Genetic diminution of circulating prothrombin ameliorates multiorgan pathologies in sickle cell disease mice.” Blood (2015). PMID: 26286849 ↗
L5OTHERCited in: 9. Hematopoietic Cell Transplantation & Cellular Therapy
[304]
Jones RJ, DeBaun MR. “Leukemia after gene therapy for sickle cell disease: insertional mutagenesis, busulfan, both, or neither.” Blood (2021). PMID: 34115136 ↗
L5OTHERCited in: 9. Hematopoietic Cell Transplantation & Cellular Therapy
[305]
Bernaudin F, Socie G, Kuentz M et al.. “Long-term results of related myeloablative stem-cell transplantation to cure sickle cell disease.” Blood (2007). PMID: 17606762 ↗
L4OTHERCited in: 9. Hematopoietic Cell Transplantation & Cellular Therapy
[306]
Sharma A, Kassim A, Thompson A et al.. “Gene Therapy for Sickle Cell Disease: Practice Recommendations from the American Society for Transplantation and Cellular Therapy and the International Society for Cell & Gene Therapy.” Transplantation and cellular therapy (2026). PMID: 41905703 ↗
L1GUIDELINECited in: 9. Hematopoietic Cell Transplantation & Cellular Therapy, History and Evolution of Treatment
[307]
Hosoya H, Levine J, Abt P et al.. “Toward dual hematopoietic stem-cell transplantation and solid-organ transplantation for sickle-cell disease.” Blood advances (2018). PMID: 29535106 ↗
L5REVIEW_NARRATIVECited in: 9. Hematopoietic Cell Transplantation & Cellular Therapy, 11. Complications
[308]
Kinoshita H, Mandava M, Jensen-Wachspress M et al.. “Outcomes following posttransplant virus-specific T-cell therapy in patients with sickle cell disease.” Blood advances (2023). PMID: 36516084 ↗
L4OTHERCited in: 9. Hematopoietic Cell Transplantation & Cellular Therapy, 11. Complications
[309]
Leonard A, Furstenau D, Abraham A et al.. “Reduction in vaso-occlusive events following stem cell transplantation in patients with sickle cell disease.” Blood advances (2023). PMID: 36240296 ↗
L2OTHERCited in: 9. Hematopoietic Cell Transplantation & Cellular Therapy
[310]
Shenoy S, Kanter J, Kassim A et al.. “A road map for uniform, comprehensive long-term follow-up after curative therapy for sickle cell disease.” Blood advances (2025). PMID: 39993235 ↗
L5REVIEW_NARRATIVECited in: 9. Hematopoietic Cell Transplantation & Cellular Therapy
[311]
Jones RJ, Kassim AA, Brodsky RA et al.. “Is allogeneic transplantation for sickle cell disease still relevant in the era of gene therapy?” Blood advances (2025). PMID: 39602668 ↗
L5REVIEW_NARRATIVECited in: 9. Hematopoietic Cell Transplantation & Cellular Therapy
[312]
Tanhehco YC, Thibodeaux S, Shi PA et al.. “Challenges and limitations of mobilization and stem cell collection for gene therapy of sickle cell disease.” Blood advances (2025). PMID: 41396678 ↗
L5REVIEW_NARRATIVECited in: 9. Hematopoietic Cell Transplantation & Cellular Therapy, 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), History and Evolution of Treatment
[313]
Magnani A, Pondarré C, Bouazza N et al.. “Extensive multilineage analysis in patients with mixed chimerism after allogeneic transplantation for sickle cell disease: insight into hematopoiesis and engraftment thresholds for gene therapy.” Haematologica (2019). PMID: 31537695 ↗
L4OTHERCited in: 9. Hematopoietic Cell Transplantation & Cellular Therapy
[314]
Arnold SD, Brazauskas R, He N et al.. “Clinical risks and healthcare utilization of hematopoietic cell transplantation for sickle cell disease in the USA using merged databases.” Haematologica (2017). PMID: 28818869 ↗
L2OTHERCited in: 9. Hematopoietic Cell Transplantation & Cellular Therapy
[315]
Andreani M, Testi M, Gaziev J et al.. “Quantitatively different red cell/nucleated cell chimerism in patients with long-term, persistent hematopoietic mixed chimerism after bone marrow transplantation for thalassemia major or sickle cell disease.” Haematologica (2010). PMID: 20935000 ↗
L4OTHERCited in: 9. Hematopoietic Cell Transplantation & Cellular Therapy
[316]
Kharya G, Nirmal G, Chadha V et al.. “Shifting paradigms from myeloablation to immune modulation: pre-transplant immune-suppression and post-transplant cyclophosphamide in human leucocyte antigen identical related donor hematopoietic stem cell transplantation for sickle cell disease.” Haematologica (2026). PMID: 42131937 ↗
L5OTHERCited in: 9. Hematopoietic Cell Transplantation & Cellular Therapy
[317]
Arnold SD, Bhatia M, Horan J et al.. “Haematopoietic stem cell transplantation for sickle cell disease - current practice and new approaches.” British journal of haematology (2016). PMID: 27255787 ↗
L5REVIEW_NARRATIVECited in: 9. Hematopoietic Cell Transplantation & Cellular Therapy
[318]
Leonard A, Tisdale J, Abraham A. “Curative options for sickle cell disease: haploidentical stem cell transplantation or gene therapy?” British journal of haematology (2020). PMID: 32034776 ↗
L5REVIEW_NARRATIVECited in: 9. Hematopoietic Cell Transplantation & Cellular Therapy
[319]
Peters C. “Haematopoietic stem cell transplantation in children with sickle cell disease: Still to do?” British journal of haematology (2023). PMID: 37957026 ↗
L5OTHERCited in: 9. Hematopoietic Cell Transplantation & Cellular Therapy
[320]
Strocchio L, Zecca M, Comoli P et al.. “Treosulfan-based conditioning regimen for allogeneic haematopoietic stem cell transplantation in children with sickle cell disease.” British journal of haematology (2015). PMID: 25818248 ↗
L4OTHERCited in: 9. Hematopoietic Cell Transplantation & Cellular Therapy
[321]
Dedeken L, Lê PQ, Azzi N et al.. “Haematopoietic stem cell transplantation for severe sickle cell disease in childhood: a single centre experience of 50 patients.” British journal of haematology (2014). PMID: 24433465 ↗
L4OTHERCited in: 9. Hematopoietic Cell Transplantation & Cellular Therapy
[322]
Felfly H, Trudel M. “Successful correction of murine sickle cell disease with reduced stem cell requirements reinforced by fractionated marrow infusions.” British journal of haematology (2009). PMID: 19930185 ↗
L5OTHERCited in: 9. Hematopoietic Cell Transplantation & Cellular Therapy
[323]
Panepinto JA, Walters MC, Carreras J et al.. “Matched-related donor transplantation for sickle cell disease: report from the Center for International Blood and Transplant Research.” British journal of haematology (2007). PMID: 17459050 ↗
L4OTHERCited in: 9. Hematopoietic Cell Transplantation & Cellular Therapy
[324]
Folarin M, Al-Zubaidi H, Moore E et al.. “Efficacy and Safety of Allogeneic Hematopoietic Stem Cell Transplantation in Curing Sickle Cell Disease: A Systematic Review and Meta-Analysis of Single-Arm Studies.” Transplantation and cellular therapy (2025). PMID: 40953733 ↗
L1SR_OBSCited in: 9. Hematopoietic Cell Transplantation & Cellular Therapy
[325]
Javed D, Rai AK, Bansal S et al.. “Efficacy of Ayurveda Regimen as an Adjunct to Hydroxyurea in Sickle Cell Disease: Protocol for a Prospective, Randomized, Open-Label, Blinded End Point Exploratory Study.” JMIR research protocols (2026). PMID: 42054235 ↗
L5TRIAL_NONRANDOMCited in: 9. Hematopoietic Cell Transplantation & Cellular Therapy, History and Evolution of Treatment
[326]
Colombatti R, Reggiani G. “Optimizing the "right" patient selection for treatment for sickle cell disease.” Hematology. American Society of Hematology. Education Program (2025). PMID: 41348018 ↗
L5CASE_REPORTCited in: 9. Hematopoietic Cell Transplantation & Cellular Therapy
[327]
Maggio A, Kattamis A, Felisi M et al.. “Evaluation of the efficacy and safety of deferiprone compared with deferasirox in paediatric patients with transfusion-dependent haemoglobinopathies (DEEP-2): a multicentre, randomised, open-label, non-inferiority, phase 3 trial.” The Lancet. Haematology (2020). PMID: 32470438 ↗
L1RCTCited in: 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), History and Evolution of Treatment
[328]
Murad MH, Liem RI, Lang ES et al.. “2019 sickle cell disease guidelines by the American Society of Hematology: methodology, challenges, and innovations.” Blood advances (2019). PMID: 31794603 ↗
L1GUIDELINECited in: 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)
[329]
Lizarralde-Iragorri MA, Parachalil Gopalan B, Merriweather B et al.. “Isoquercetin for thromboinflammation in sickle cell disease: a randomized double-blind placebo-controlled trial.” Blood advances (2024). PMID: 38157227 ↗
L1RCTCited in: 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), History and Evolution of Treatment, 12. Prognosis & Natural History
[330]
Wolf J, Blais-Normandin I, Bathla A et al.. “Red cell specifications for blood group matching in patients with haemoglobinopathies: An updated systematic review and clinical practice guideline from the International Collaboration for Transfusion Medicine Guidelines.” British journal of haematology (2024). PMID: 39535318 ↗
L2GUIDELINECited in: 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)
[331]
Howard J, Malfroy M, Llewelyn C et al.. “The Transfusion Alternatives Preoperatively in Sickle Cell Disease (TAPS) study: a randomised, controlled, multicentre clinical trial.” Lancet (London, England) (2013). PMID: 23352054 ↗
L1RCTCited in: 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), History and Evolution of Treatment, 11. Complications, 12. Prognosis & Natural History
[332]
Chou ST, Hendrickson JE. “How I treat challenging transfusion cases in sickle cell disease.” Blood (2025). PMID: 38728382 ↗
L5CASE_REPORTCited in: 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), 12. Prognosis & Natural History
[333]
Verduzco LA, Nathan DG. “Sickle cell disease and stroke.” Blood (2009). PMID: 19797523 ↗
L5REVIEW_NARRATIVECited in: 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)
[334]
DeBaun MR, Kirkham FJ. “Central nervous system complications and management in sickle cell disease.” Blood (2016). PMID: 26758917 ↗
L5REVIEW_NARRATIVECited in: 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), History and Evolution of Treatment, 14. Prevention, Screening & Surveillance
[335]
Kato GJ. “Sickle cells and sickle trait in thrombosis.” Blood (2019). PMID: 31171540 ↗
L5OTHERCited in: 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)
[336]
Bannow BS, Akpan I, Baldwin MK. “Female reproductive health-what the classical haematologist needs to know.” The Lancet. Haematology (2026). PMID: 42302802 ↗
L5REVIEW_NARRATIVECited in: 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), 13. Special Populations & Pregnancy
[337]
Zheng Y, Gossett JM, Chen PL et al.. “Proinflammatory state promotes red blood cell alloimmunization in pediatric patients with sickle cell disease.” Blood advances (2023). PMID: 37023228 ↗
L3OTHERCited in: 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)
[338]
Fogarty H, Ahmad A, Atiq F et al.. “VWF-ADAMTS13 axis dysfunction in children with sickle cell disease treated with hydroxycarbamide vs blood transfusion.” Blood advances (2023). PMID: 37773926 ↗
L3OTHERCited in: 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)
[339]
Yaseen A, Suleiman S, Zenah OA et al.. “Red blood-cell alloantibodies in multiply transfused patients in the occupied Palestinian territory: a pilot study.” Lancet (London, England) (2018). PMID: 29553439 ↗
L4OTHERCited in: 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), 12. Prognosis & Natural History, 14. Prevention, Screening & Surveillance
[340]
Gotardo ÉMF, Torres LS, Zaidan BC et al.. “Targeting P-selectin and interleukin-1β in mice with sickle cell disease: effects on vaso-occlusion, liver injury and organ iron deposition.” Haematologica (2025). PMID: 39568425 ↗
L5OTHERCited in: 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)
[341]
Mattè A, Federti E, Recchiuti A et al.. “Epeleuton, a novel synthetic ω-3 fatty acid, reduces hypoxia/ reperfusion stress in a mouse model of sickle cell disease.” Haematologica (2024). PMID: 38105727 ↗
L5OTHERCited in: 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)
[342]
Galadanci NA, Johnson W, Carson A et al.. “Factors associated with left ventricular hypertrophy in children with sickle cell disease: results from the DISPLACE study.” Haematologica (2022). PMID: 35417940 ↗
L2OTHERCited in: 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), 14. Prevention, Screening & Surveillance
[343]
Coates TD, Wood JC. “How we manage iron overload in sickle cell patients.” British journal of haematology (2017). PMID: 28295188 ↗
L5REVIEW_NARRATIVECited in: 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)
[344]
Davila J, O'Brien SH, Mitchell WB et al.. “Evaluating thromboprophylaxis in the sickle cell disease population: Navigating the evidence gap.” British journal of haematology (2024). PMID: 38578212 ↗
L5REVIEW_NARRATIVECited in: 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), 14. Prevention, Screening & Surveillance
[345]
Hagar W, Vichinsky E. “Advances in clinical research in sickle cell disease.” British journal of haematology (2008). PMID: 18341629 ↗
L5REVIEW_NARRATIVECited in: 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), History and Evolution of Treatment, 12. Prognosis & Natural History
[346]
Ataga KI, Cappellini MD, Rachmilewitz EA. “Beta-thalassaemia and sickle cell anaemia as paradigms of hypercoagulability.” British journal of haematology (2007). PMID: 17854302 ↗
L5REVIEW_NARRATIVECited in: 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)
[347]
Sheth S, Licursi M, Bhatia M. “Sickle cell disease: time for a closer look at treatment options?” British journal of haematology (2013). PMID: 23772687 ↗
L5REVIEW_NARRATIVECited in: 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), History and Evolution of Treatment, 14. Prevention, Screening & Surveillance
[348]
Colombatti R, Maschietto N, Varotto E et al.. “Pulmonary hypertension in sickle cell disease children under 10 years of age.” British journal of haematology (2010). PMID: 20553267 ↗
L2REVIEW_NARRATIVECited in: 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), History and Evolution of Treatment, 14. Prevention, Screening & Surveillance
[349]
Tutwiler V, Litvinov RI, Protopopova A et al.. “Pathologically stiff erythrocytes impede contraction of blood clots.” Journal of thrombosis and haemostasis : JTH (2021). PMID: 34233380 ↗
L5OTHERCited in: 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management), 11. Complications
[350]
Mehta D. “Case Report: Optimizing ICU management of sickle cell crisis: the impact of bedside ultrasound on clinical decision-making.” Frontiers in medicine (2026). PMID: 42063764 ↗
L4CASE_REPORTCited in: 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)
[351]
Sah JA, Twumasi S, Ayirebi AA et al.. “Assessing Liver and Iron Markers in Steady State Pediatric SCD Patients to Ascertain the Hepatic Consequences of Hemotransfusion: A Case-Control Study in Ghana.” Health science reports (2026). PMID: 42022665 ↗
L3CASE_CONTROLCited in: 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)
[352]
Nirmal G, Chadha V, Verma S et al.. “Safety, efficacy and feasibility of GCSF and plerixafor based CD34 mobilization for backup autologous stem cell collection in patients undergoing alternate donor hematopoietic stem cell transplant for sickle cell disease: Take away lessons for gene therapy.” Bone marrow transplantation (2026). PMID: 42342967 ↗
L4OTHERCited in: 10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)
[353]
Bartolucci P, El Murr T, Roudot-Thoraval F et al.. “A randomized, controlled clinical trial of ketoprofen for sickle-cell disease vaso-occlusive crises in adults.” Blood (2009). PMID: 19717646 ↗
L1RCTCited in: History and Evolution of Treatment
[354]
Merlet AN, Messonnier LA, Coudy-Gandilhon C et al.. “Beneficial effects of endurance exercise training on skeletal muscle microvasculature in sickle cell disease patients.” Blood (2019). PMID: 31742587 ↗
L4RCTCited in: History and Evolution of Treatment
[355]
Gellen B, Messonnier LA, Galactéros F et al.. “Moderate-intensity endurance-exercise training in patients with sickle-cell disease without severe chronic complications (EXDRE): an open-label randomised controlled trial.” The Lancet. Haematology (2018). PMID: 30389037 ↗
L1RCTCited in: History and Evolution of Treatment, 11. Complications, 13. Special Populations & Pregnancy
[356]
Koshy M, Burd L, Wallace D et al.. “Prophylactic red-cell transfusions in pregnant patients with sickle cell disease. A randomized cooperative study.” The New England journal of medicine (1988). PMID: 3054555 ↗
L1RCTCited in: History and Evolution of Treatment
[357]
Adams RJ, Brambilla D. “Discontinuing prophylactic transfusions used to prevent stroke in sickle cell disease.” The New England journal of medicine (2005). PMID: 16382063 ↗
L1RCTCited in: History and Evolution of Treatment
[358]
Griffin TC, McIntire D, Buchanan GR. “High-dose intravenous methylprednisolone therapy for pain in children and adolescents with sickle cell disease.” The New England journal of medicine (1994). PMID: 8107739 ↗
L1RCTCited in: History and Evolution of Treatment
[359]
Wilimas JA, Flynn PM, Harris S et al.. “A randomized study of outpatient treatment with ceftriaxone for selected febrile children with sickle cell disease.” The New England journal of medicine (1993). PMID: 8332152 ↗
L1RCTCited in: History and Evolution of Treatment
[360]
Vichinsky EP, Haberkern CM, Neumayr L et al.. “A comparison of conservative and aggressive transfusion regimens in the perioperative management of sickle cell disease. The Preoperative Transfusion in Sickle Cell Disease Study Group.” The New England journal of medicine (1995). PMID: 7791837 ↗
L1RCTCited in: History and Evolution of Treatment
[361]
Xu JZ, Conrey A, Frey I et al.. “A phase 1 dose escalation study of the pyruvate kinase activator mitapivat (AG-348) in sickle cell disease.” Blood (2022). PMID: 35576529 ↗
L4TRIAL_NONRANDOMCited in: History and Evolution of Treatment
[362]
Walters MC, Patience M, Leisenring W et al.. “Bone marrow transplantation for sickle cell disease.” The New England journal of medicine (1996). PMID: 8663884 ↗
L4TRIAL_NONRANDOMCited in: History and Evolution of Treatment
[363]
Falk RJ, Scheinman J, Phillips G et al.. “Prevalence and pathologic features of sickle cell nephropathy and response to inhibition of angiotensin-converting enzyme.” The New England journal of medicine (1992). PMID: 1542341 ↗
L4TRIAL_NONRANDOMCited in: History and Evolution of Treatment
[364]
Jacobson SJ, Kopecky EA, Joshi P et al.. “Randomised trial of oral morphine for painful episodes of sickle-cell disease in children.” Lancet (London, England) (1997). PMID: 9365450 ↗
L1RCTCited in: History and Evolution of Treatment
[365]
De Ceulaer K, Gruber C, Hayes R et al.. “Medroxyprogesterone acetate and homozygous sickle-cell disease.” Lancet (London, England) (1982). PMID: 6178915 ↗
L1RCTCited in: History and Evolution of Treatment
[366]
Serjeant GR, de Ceulaer K, Maude GH. “Stilboestrol and stuttering priapism in homozygous sickle-cell disease.” Lancet (London, England) (1985). PMID: 2866338 ↗
L1RCTCited in: History and Evolution of Treatment
[367]
Dabis F, Msellati P, Meda N et al.. “6-month efficacy, tolerance, and acceptability of a short regimen of oral zidovudine to reduce vertical transmission of HIV in breastfed children in Côte d'Ivoire and Burkina Faso: a double-blind placebo-controlled multicentre trial. DITRAME Study Group. DIminution de la Transmission Mère-Enfant.” Lancet (London, England) (1999). PMID: 10459959 ↗
L1RCTCited in: History and Evolution of Treatment
[368]
de Montalembert M, Bachir D, Hulin A et al.. “Pharmacokinetics of hydroxyurea 1,000 mg coated breakable tablets and 500 mg capsules in pediatric and adult patients with sickle cell disease.” Haematologica (2006). PMID: 17145606 ↗
L1RCTCited in: History and Evolution of Treatment, 13. Special Populations & Pregnancy
[369]
de Montalembert M, Brousse V, Elie C et al.. “Long-term hydroxyurea treatment in children with sickle cell disease: tolerance and clinical outcomes.” Haematologica (2006). PMID: 16434381 ↗
L4TRIAL_NONRANDOMCited in: History and Evolution of Treatment
[370]
Schechter AN. “Hemoglobin research and the origins of molecular medicine.” Blood (2008). PMID: 18988877 ↗
L5REVIEW_NARRATIVECited in: History and Evolution of Treatment
[371]
Wilber A, Nienhuis AW, Persons DA. “Transcriptional regulation of fetal to adult hemoglobin switching: new therapeutic opportunities.” Blood (2011). PMID: 21321359 ↗
L5REVIEW_NARRATIVECited in: History and Evolution of Treatment
[372]
Dembélé AK, Lapoumeroulie C, Diaw M et al.. “Cell-derived microparticles and sickle cell disease chronic vasculopathy in sub-Saharan Africa: A multinational study.” British journal of haematology (2020). PMID: 33249569 ↗
L3TRIAL_NONRANDOMCited in: History and Evolution of Treatment
[373]
Vichinsky EP, Lubin BH. “A cautionary note regarding hydroxyurea in sickle cell disease.” Blood (1994). PMID: 7509209 ↗
L4CASE_REPORTCited in: History and Evolution of Treatment
[374]
Dutta D, Aujla A, Knoll BM et al.. “Intestinal pathophysiological and microbial changes in sickle cell disease: Potential targets for therapeutic intervention.” British journal of haematology (2019). PMID: 31693163 ↗
L5REVIEW_NARRATIVECited in: History and Evolution of Treatment
[375]
Kato GJ, Taylor JG. “Pleiotropic effects of intravascular haemolysis on vascular homeostasis.” British journal of haematology (2009). PMID: 19958359 ↗
L5REVIEW_NARRATIVECited in: History and Evolution of Treatment
[376]
Haverfield EV, McKenzie CA, Forrester T et al.. “UGT1A1 variation and gallstone formation in sickle cell disease.” Blood (2004). PMID: 15388579 ↗
L2OTHERCited in: History and Evolution of Treatment
[377]
Platt OS, Thorington BD, Brambilla DJ et al.. “Pain in sickle cell disease. Rates and risk factors.” The New England journal of medicine (1991). PMID: 1710777 ↗
L2OTHERCited in: History and Evolution of Treatment
[378]
Saraf SL, Akingbola TS, Shah BN et al.. “Associations of α-thalassemia and BCL11A with stroke in Nigerian, United States, and United Kingdom sickle cell anemia cohorts.” Blood advances (2017). PMID: 28868518 ↗
L2OTHERCited in: History and Evolution of Treatment
[379]
Ghunney WK, Asare EV, Ayete-Nyampong JB et al.. “Most adults with severe HbSC disease are not treated with hydroxyurea.” Blood advances (2023). PMID: 36799926 ↗
L4OTHERCited in: History and Evolution of Treatment
[380]
Brandsen RP, Diederen RMH, Bakhlakh S et al.. “Natural history and rate of progression of retinopathy in adult patients with sickle cell disease: an 11-year follow-up study.” Blood advances (2023). PMID: 36897257 ↗
L2OTHERCited in: History and Evolution of Treatment
[381]
Christakis J, Vavatsi N, Hassapopoulou H et al.. “Comparison of homozygous sickle cell disease in northern Greece and Jamaica.” Lancet (London, England) (1990). PMID: 1690325 ↗
L4OTHERCited in: History and Evolution of Treatment
[382]
Onwubalili JK. “Sickle-cell anaemia: an explanation for the ancient myth of reincarnation in Nigeria.” Lancet (London, England) (1983). PMID: 6136656 ↗
L5OTHERCited in: History and Evolution of Treatment
[383]
Shet AS, Lizarralde-Iragorri MA, Naik RP. “The molecular basis for the prothrombotic state in sickle cell disease.” Haematologica (2020). PMID: 33054077 ↗
L5OTHERCited in: History and Evolution of Treatment
[384]
van Beers EJ, van Tuijn CF, Mac Gillavry MR et al.. “Sickle cell disease-related organ damage occurs irrespective of pain rate: implications for clinical practice.” Haematologica (2008). PMID: 18367483 ↗
L2OTHERCited in: History and Evolution of Treatment
[385]
Odièvre MH, Bony V, Benkerrou M et al.. “Modulation of erythroid adhesion receptor expression by hydroxyurea in children with sickle cell disease.” Haematologica (2008). PMID: 18322255 ↗
L4OTHERCited in: History and Evolution of Treatment
[386]
Early ML, Luo A, Solow M et al.. “Natural history of blood pressure in sickle cell disease pregnancy.” British journal of haematology (2023). PMID: 37803527 ↗
L2OTHERCited in: History and Evolution of Treatment, 13. Special Populations & Pregnancy
[387]
Manganas K, Delicou S, Xydaki A et al.. “Predisposing factors for advanced liver fibrosis in patients with sickle cell disease.” British journal of haematology (2023). PMID: 37438880 ↗
L4OTHERCited in: History and Evolution of Treatment
[388]
Babatunde OO, Bibby MG, Atala A et al.. “Sickle Cell Disease: Historical Overview and Current Therapies.” Prenatal diagnosis (2026). PMID: 42272061 ↗
L5REVIEW_NARRATIVECited in: History and Evolution of Treatment
[389]
Sharma A, Suryaprakash S, Johnson LM et al.. “Discontinued therapies for sickle cell disease: status and future directions.” Expert opinion on investigational drugs (2026). PMID: 42007797 ↗
L5REVIEW_NARRATIVECited in: History and Evolution of Treatment
[390]
Ataga KI. “Natural History of Chronic Kidney Disease in Sickle Cell Disease.” American journal of hematology (2026). PMID: 41927315 ↗
L5REVIEW_NARRATIVECited in: History and Evolution of Treatment
[391]
Therrell BL. “Newborn Screening for Hemoglobinopathies and Thalassemias: Brief History, Recent Activities, and Global Status-2026.” International journal of neonatal screening (2026). PMID: 41718422 ↗
L5REVIEW_NARRATIVECited in: History and Evolution of Treatment
[392]
Bafunyembaka G, Nacher M, Maniassom C et al.. “Asthma and overt stroke in children with sickle cell disease: a multicenter pediatric cohort study in French Guiana.” BMC pediatrics (2026). PMID: 42387435 ↗
L2COHORTCited in: History and Evolution of Treatment, 13. Special Populations & Pregnancy
[393]
Adetoye E, Adebanwo A, Banjo F et al.. “Neurological manifestations in Nigerian children with sickle cell disease: a single-center retrospective study.” BMC pediatrics (2026). PMID: 42337449 ↗
L4COHORTCited in: History and Evolution of Treatment, 12. Prognosis & Natural History, 13. Special Populations & Pregnancy
[394]
Earley EJ, Kelly S, Fang F et al.. “Genome-wide association study of early ischaemic stroke risk in Brazilian individuals with sickle cell disease implicates ADAMTS2 and CDK18 and uncovers novel loci.” British journal of haematology (2023). PMID: 36602125 ↗
L3SR_OBSCited in: 11. Complications
[395]
Ladu AI, Aiyenigba AO, Adekile A et al.. “The spectrum of splenic complications in patients with sickle cell disease in Africa: a systematic review.” British journal of haematology (2020). PMID: 33161568 ↗
L2SR_OBSCited in: 11. Complications
[396]
Liu Y, Shayo S, Su S et al.. “Heme-induced activation of the TLR3/TRIF-IFN-I-CCL2 pathway contributes to kidney injury in sickle cell disease.” Blood (2026). PMID: 41481385 ↗
L5OTHERCited in: 11. Complications
[397]
Beri D, Rodriguez M, Singh M et al.. “Babesiosis and sickle red blood cells: loss of deformability, altered osmotic fragility, and hypervesiculation.” Blood (2025). PMID: 39869831 ↗
L5OTHERCited in: 11. Complications
[398]
Yazdanbakhsh K, Ware RE, Noizat-Pirenne F. “Red blood cell alloimmunization in sickle cell disease: pathophysiology, risk factors, and transfusion management.” Blood (2012). PMID: 22563085 ↗
L5REVIEW_NARRATIVECited in: 11. Complications
[399]
Kumari N, Nouraie M, Ahmad A et al.. “Restriction of HIV-1 infection in sickle cell trait.” Blood advances (2021). PMID: 34496009 ↗
L5OTHERCited in: 11. Complications
[400]
Scourfield LEA, Nardo-Marino A, Williams TN et al.. “Infections in sickle cell disease.” Haematologica (2025). PMID: 39568431 ↗
L5REVIEW_NARRATIVECited in: 11. Complications, 12. Prognosis & Natural History
[401]
Brousse V, Buffet P, Rees D. “The spleen and sickle cell disease: the sick(led) spleen.” British journal of haematology (2014). PMID: 24862308 ↗
L5REVIEW_NARRATIVECited in: 11. Complications
[402]
O'Hanlon Cohrt K, O'Dea S. “Clinical Trial Landscape of Gene-Edited Autologous Hematopoietic Stem Cells for Hemoglobinopathies and Immunodeficiencies.” International journal of molecular sciences (2026). PMID: 42074029 ↗
L5TRIAL_NONRANDOMCited in: 11. Complications
[403]
Malinowski AK, Shehata N, D'Souza R et al.. “Prophylactic transfusion for pregnant women with sickle cell disease: a systematic review and meta-analysis.” Blood (2015). PMID: 26302758 ↗
L1SR_OBSCited in: 12. Prognosis & Natural History, 13. Special Populations & Pregnancy
[404]
Walters MC, Eapen M, Liu Y et al.. “Hematopoietic cell transplant compared with standard care in adolescents and young adults with sickle cell disease.” Blood advances (2025). PMID: 39471440 ↗
L2TRIAL_NONRANDOMCited in: 12. Prognosis & Natural History
[405]
Jiao B, Johnson KM, Ramsey SD et al.. “Long-term survival with sickle cell disease: a nationwide cohort study of Medicare and Medicaid beneficiaries.” Blood advances (2023). PMID: 36929166 ↗
L3COHORTCited in: 12. Prognosis & Natural History
[406]
Ranque B, Kitenge R, Ndiaye DD et al.. “Estimating the risk of child mortality attributable to sickle cell anaemia in sub-Saharan Africa: a retrospective, multicentre, case-control study.” The Lancet. Haematology (2022). PMID: 35240076 ↗
L3CASE_CONTROLCited in: 12. Prognosis & Natural History, 14. Prevention, Screening & Surveillance
[407]
Maitra P, Caughey M, Robinson L et al.. “Risk factors for mortality in adult patients with sickle cell disease: a meta-analysis of studies in North America and Europe.” Haematologica (2017). PMID: 28104703 ↗
L2SR_OBSCited in: 12. Prognosis & Natural History
[408]
Stenger EO, Shenoy S, Krishnamurti L. “How I treat sickle cell disease with hematopoietic cell transplantation.” Blood (2019). PMID: 31697818 ↗
L5CASE_REPORTCited in: 12. Prognosis & Natural History
[409]
Gardner K, Suddle A, Kane P et al.. “How we treat sickle hepatopathy and liver transplantation in adults.” Blood (2014). PMID: 24565828 ↗
L5CASE_REPORTCited in: 12. Prognosis & Natural History
[410]
Tumblin A, Tailor A, Hoehn GT et al.. “Apolipoprotein A-I and serum amyloid A plasma levels are biomarkers of acute painful episodes in patients with sickle cell disease.” Haematologica (2010). PMID: 20378559 ↗
L4OTHERCited in: 12. Prognosis & Natural History
[411]
Tubman VN, Makani J. “Turf wars: exploring splenomegaly in sickle cell disease in malaria-endemic regions.” British journal of haematology (2017). PMID: 28493472 ↗
L5REVIEW_NARRATIVECited in: 12. Prognosis & Natural History
[412]
Højagergaard MA, Thønnings S, Søes LM et al.. “Antibiotic Treatment Duration for Salmonella Osteoarticular Infections in Children - A Systematic Review and Comparative Study.” Acta paediatrica (Oslo, Norway : 1992) (2026). PMID: 42059540 ↗
L4SR_OBSCited in: 12. Prognosis & Natural History
[413]
Ford AL, Ragan DK, Fellah S et al.. “Silent infarcts in sickle cell disease occur in the border zone region and are associated with low cerebral blood flow.” Blood (2018). PMID: 30061156 ↗
L2RCTCited in: 13. Special Populations & Pregnancy
[414]
Brothers RO, Turrentine KB, Akbar M et al.. “The influence of voxelotor on cerebral blood flow and oxygen extraction in pediatric sickle cell disease.” Blood (2024). PMID: 38364110 ↗
L4TRIAL_NONRANDOMCited in: 13. Special Populations & Pregnancy
[415]
Oteng-Ntim E, Meeks D, Seed PT et al.. “Adverse maternal and perinatal outcomes in pregnant women with sickle cell disease: systematic review and meta-analysis.” Blood (2015). PMID: 25800049 ↗
L2SR_OBSCited in: 13. Special Populations & Pregnancy
[416]
Minniti CP, Sable C, Campbell A et al.. “Elevated tricuspid regurgitant jet velocity in children and adolescents with sickle cell disease: association with hemolysis and hemoglobin oxygen desaturation.” Haematologica (2009). PMID: 19211639 ↗
L4TRIAL_NONRANDOMCited in: 13. Special Populations & Pregnancy
[417]
Davila J, Stanek J, O'Brien SH. “Venous thromboembolism prophylaxis in sickle cell disease: a multicenter cohort study of adolescent inpatients.” Blood advances (2023). PMID: 37103974 ↗
L3COHORTCited in: 13. Special Populations & Pregnancy
[418]
Oakley LL, Mitchell S, von Rege I et al.. “Perinatal outcomes in women with sickle cell disease: a matched cohort study from London, UK.” British journal of haematology (2021). PMID: 34881428 ↗
L3COHORTCited in: 13. Special Populations & Pregnancy
[419]
Yuan S, Jordan LC, Davis LT et al.. “A cross-sectional, case-control study of intracranial arterial wall thickness and complete blood count measures in sickle cell disease.” British journal of haematology (2020). PMID: 33326595 ↗
L3CASE_CONTROLCited in: 13. Special Populations & Pregnancy
[420]
James AH, Strouse JJ. “How I treat sickle cell disease in pregnancy.” Blood (2024). PMID: 37979134 ↗
L5OTHERCited in: 13. Special Populations & Pregnancy
[421]
Schaer DJ, Buehler PW, Alayash AI et al.. “Hemolysis and free hemoglobin revisited: exploring hemoglobin and hemin scavengers as a novel class of therapeutic proteins.” Blood (2012). PMID: 23264591 ↗
L5REVIEW_NARRATIVECited in: 13. Special Populations & Pregnancy
[422]
van Langevelde K, Flinterman LE, van Hylckama Vlieg A et al.. “Broadening the factor V Leiden paradox: pulmonary embolism and deep-vein thrombosis as 2 sides of the spectrum.” Blood (2012). PMID: 22496157 ↗
L3REVIEW_NARRATIVECited in: 13. Special Populations & Pregnancy
[423]
Guarino SH, Jain A, Madisetti M et al.. “National Alliance of Sickle Cell Centers consensus standards for transition to adult care in sickle cell disease.” Blood advances (2025). PMID: 40472332 ↗
L5OTHERCited in: 13. Special Populations & Pregnancy
[424]
Sharma D, Kozanoğlu I, Ataga KI et al.. “Managing sickle cell disease and related complications in pregnancy: results of an international Delphi panel.” Blood advances (2024). PMID: 38206762 ↗
L5OTHERCited in: 13. Special Populations & Pregnancy
[425]
Colombatti R, Dalla Pozza LV, Mazzucato M et al.. “Hospitalization of children with sickle cell disease in a region with increasing immigration rates.” Haematologica (2008). PMID: 18310539 ↗
L4OTHERCited in: 13. Special Populations & Pregnancy
[426]
Bulbul Z, Zareef R, Nassif TA et al.. “Left ventricular strain and chamber dimensions in pediatric sickle cell disease: age-related reduction in myocardial deformation independent of hemolysis and hydroxyurea therapy.” Haematologica (2025). PMID: 41414968 ↗
L3OTHERCited in: 13. Special Populations & Pregnancy
[427]
Pecker LH, Sharma D, Nero A et al.. “Knowledge gaps in reproductive and sexual health in girls and women with sickle cell disease.” British journal of haematology (2021). PMID: 34231198 ↗
L5REVIEW_NARRATIVECited in: 13. Special Populations & Pregnancy
[428]
Sil S, Mooney JT, Adkins TR et al.. “I-STRONG: an integrative, multicomponent treatment approach for chronic pain in pediatric sickle cell disease.” Blood advances (2026). PMID: 42024471 ↗
L4TRIAL_NONRANDOMCited in: 13. Special Populations & Pregnancy
[429]
Vilela TS, Fisberg M, Ferrari G et al.. “A systematic review on clinical and laboratory effects of vitamin D deficiency in children with sickle cell disease.” Nutrition and health (2026). PMID: 42339751 ↗
L2SR_OBSCited in: 13. Special Populations & Pregnancy
[430]
Field TS, Selvanathan T. “Stroke in Children and Younger Adults.” Continuum (Minneapolis, Minn.) (2026). PMID: 42233825 ↗
L5CASE_REPORTCited in: 13. Special Populations & Pregnancy
[431]
Anele UA, Le BV, Resar LM et al.. “How I treat priapism.” Blood (2015). PMID: 25810489 ↗
L5OTHERCited in: 14. Prevention, Screening & Surveillance
[432]
Wood JC. “Brain O2 reserve in sickle cell disease.” Blood (2019). PMID: 31147375 ↗
L5OTHERCited in: 14. Prevention, Screening & Surveillance
[433]
Ranque B, Menet A, Diop IB et al.. “Early renal damage in patients with sickle cell disease in sub-Saharan Africa: a multinational, prospective, cross-sectional study.” The Lancet. Haematology (2014). PMID: 27030156 ↗
L4OTHERCited in: 14. Prevention, Screening & Surveillance
[434]
Green NS, Zapfel A, Nnodu OE et al.. “The Consortium on Newborn Screening in Africa for sickle cell disease: study rationale and methodology.” Blood advances (2022). PMID: 36264096 ↗
L5OTHERCited in: 14. Prevention, Screening & Surveillance
[435]
Alvarez OA, St Victor Dély N, Paul Hanna M et al.. “Implementation of hospital-based sickle cell newborn screening and follow-up programs in Haiti.” Blood advances (2024). PMID: 37820110 ↗
L4OTHERCited in: 14. Prevention, Screening & Surveillance
[436]
Adamkiewicz TV, Yee MEM, Thomas S et al.. “Pneumococcal infections in children with sickle cell disease before and after pneumococcal conjugate vaccines.” Blood advances (2023). PMID: 37698500 ↗
L2OTHERCited in: 14. Prevention, Screening & Surveillance
[437]
Mancini M, Buffet A, Porte B et al.. “EPAS1-mutated paragangliomas associated with haemoglobin disorders.” British journal of haematology (2024). PMID: 38195958 ↗
L4OTHERCited in: 14. Prevention, Screening & Surveillance
[438]
Naveed F, Tao BK, Ashamalla M et al.. “Association of hydroxyurea use and sickle cell retinopathy: A systematic review and meta-analysis.” Survey of ophthalmology (2026). PMID: 42242558 ↗
L2SR_OBSCited in: 14. Prevention, Screening & Surveillance
[439]
Gangwar M, Kumar G, Roy S et al.. “Study protocol for a randomized, double-blind, placebo-controlled clinical trial of desidustat oral tablet in sickle cell disease: a phase IIa proof-of-concept evaluation.” Trials (2026). PMID: 42106815 ↗
L5TRIAL_NONRANDOMCited in: 14. Prevention, Screening & Surveillance
[440]
Abacan MAR, Baltazar-Braganza KR, Cabaluna ITG et al.. “Philippine Clinical Practice Guidelines for Periodic Health Examination: Screening for Congenital and Developmental Disorders.” Acta medica Philippina (2026). PMID: 42382931 ↗
L1GUIDELINECited in: 14. Prevention, Screening & Surveillance

Quick Reference

Overview and Recommendations

Background

Evaluation

Management

Board Review — High Yield

Deep Dive — Evidence Details

1. Definition, Classification & Nomenclature

Also Called / Synonyms

Classification of Major Genotypes

Clinical Significance

2. Pathophysiology & Mechanism

HbS Polymerization and Erythrocyte Sickling

Hemolysis and the Heme-Inflammatory Axis

Vaso-Occlusion and Thromboinflammation

Oxidative Stress and Metabolic Reprogramming

End-Organ Damage: A Shared Final Pathway

Genetic Modifiers and Phenotypic Heterogeneity

3. Epidemiology, Etiology & Risk Factors

Genotype, Modifiers, and Clinical Risk Factors

Seasonal and Environmental Variation

Health Disparities

4. Clinical Presentation

Presenting Symptoms

Neurological Examination Findings

Phenotypic Variants

Red Flags

Atypical Presentations

5. Diagnosis & Workup: Smear, Marrow, Flow Cytometry & Molecular Profiling

Peripheral Blood Smear

Bone Marrow Examination

Flow Cytometry

Molecular and Genetic Testing

6. Staging, Risk Stratification & Prognostic Scoring

Validated Prognostic Scores

Key Prognostic Factors

Emerging Biomarkers

Risk Stratification in Clinical Practice

7. Acute & Emergency Management

Step 1: Triage and Immediate Assessment

Step 2: Analgesia - First-Line and Escalation

Step 3: Acute Chest Syndrome - Recognition and Respiratory Support

Step 4: Acute Stroke and Priapism

Step 5: Transition to Definitive Management

Controversies and Guideline Disagreement

8. Long-term & Definitive Management

Step 1: Initiate Hydroxyurea as First-Line Disease-Modifying Therapy

Step 2: Add or Switch to Novel Oral Agents When Response Is Inadequate

Drug / Modality Comparison Table

Step 3: Refer for Curative Therapy - Hematopoietic Stem Cell Transplantation or Gene Therapy

Controversies and Guideline Disagreement

What NOT to Do

9. Hematopoietic Cell Transplantation & Cellular Therapy

Allogeneic Hematopoietic Stem Cell Transplantation

Autologous Gene Therapy and Gene Editing

Controversies and Guideline Disagreement

10. Transfusion, Anticoagulation & Cytoreduction (Hematology-Distinctive Management)

Transfusion Support

Anticoagulation

Disease-Modifying Therapy

Controversies and Guideline Disagreement

History and Evolution of Treatment

The Hydroxyurea Era

Targeted Therapies: 2017-2019

Disappointments and Lessons

Emerging Small Molecules

From Transplant to Gene Therapy

The Road Ahead

11. Complications

Respiratory Monitoring

Autonomic and Other Complications

Pain Management

Rehabilitation

Hospital-Acquired Complication Prevention

12. Prognosis & Natural History

Risk Factors for Mortality in Adults

Natural History and Modifying Factors

13. Special Populations & Pregnancy

Pregnancy

Step 2: - First-Line and Escalation