bims-sicedi Biomed News
on Sickle cell disease
Issue of 2025–12–07
nine papers selected by
João Conrado Khouri dos Santos, Universidade de São Paulo



  1. Hum Mol Genet. 2025 Dec 05. pii: ddaf179. [Epub ahead of print]
      Fetal hemoglobin (HbF) modulates the clinical severity of sickle cell disease (SCD) by inhibiting the polymerization of sickle hemoglobin. Elevated HbF levels are associated with milder disease phenotypes, fewer Vaso-occlusive crises, and reduced organ damage. Understanding the molecular regulation of HbF expression is critical for the development of new therapeutic strategies, including pharmacologic agents and gene-based interventions aimed at ameliorating the course of SCD. We investigated transcriptomic expression in erythroid cells during the transition from the neonatal period to early childhood to identify genes associated with HbF regulation. Reticulocyte transcriptomes were compared between samples obtained at birth (cord blood), when HbF levels ranged from 72.6% to 90%, and at 18 months of age (whole blood), when HbF levels declined to 5.9%-10.3%. Reticulocytes were enriched, RNA extracted, and high-throughput RNA sequencing was performed, followed by differential gene expression and network analyses. Analysis of 20 346 genes revealed 1245 differentially expressed genes, of which 631 genes were upregulated in cord blood reticulocytes. The differentially expressed genes were significantly enriched in pathways related to cell signaling, proliferation, differentiation, metabolism, immune functionality, and erythropoiesis. Developmental shifts in the erythroid transcriptome uncover key biological processes that may regulate HbF expression. These findings offer a valuable panel of candidate genes for future functional studies and highlight new potential molecular targets for therapeutic modulation of HbF in sickle cell disease.
    Keywords:  Fetal haemoglobin; Reticulocyte; Transcriptome; sickle cell disease
    DOI:  https://doi.org/10.1093/hmg/ddaf179
  2. Hematology Am Soc Hematol Educ Program. 2025 Dec 05. 2025(1): 511-522
      Pregnancy is high risk for individuals with sickle cell disease (SCD), and maternal morbidity and mortality are unchanged in middle- and high-income settings. As many as 30% of SCD pregnancies may be uncomplicated, but most are associated with complications. The odds of severe maternal morbidity are much higher in Black women with SCD than in Black women without SCD or non-Black women. Prophylactic red cell transfusions are considered low risk according to American Society of Hematology guidelines and are the only disease-modifying therapy available for use in pregnancy. When initiated in the preconception and/or prenatal period, treatment is associated with reduced maternal and fetal mortality, painful crises, and pulmonary complications in pregnancy. Furthermore, pain occurs in as many as 75% of SCD pregnancies; in meta-analyses and randomized controlled data, transfusions reduce pain events during SCD pregnancy. British, American, and French guidelines make recommendations regarding transfusion indications in SCD pregnancy. Many people with SCD, and most with hemoglobin SS or hemoglobin Sβ0-thalassemia, have an indication for prophylactic transfusion during pregnancy. Transfusion may meaningfully improve outcomes for pregnant people with SCD. We discuss our approach to managing SCD pregnancy using the case of a patient cared for in the mid-Atlantic region of the United States.
    DOI:  https://doi.org/10.1182/hematology.2025000744
  3. Hematology Am Soc Hematol Educ Program. 2025 Dec 05. 2025(1): 279-284
      Sickle cell disease (SCD) is an acquired hypercoagulable state defined by the presence of prothrombotic alterations of the coagulation system, increased platelet activation, and endothelial disruption. These changes are associated with increased incidence of venous thromboembolism (VTE). There is interest in investigating the role of primary thromboprophylaxis, especially with the use of central venous catheters, perioperatively and during the last trimester of pregnancy and postpartum. Like the general population of patients with VTE, direct oral anti-Xa antagonists are being widely used as anticoagulation for secondary prophylaxis.
    DOI:  https://doi.org/10.1182/hematology.2025000715C
  4. Am J Hematol. 2025 Dec 03.
      Chronic kidney disease (CKD) is common and a major contributor to increased morbidity and early mortality in people with sickle cell anemia (SCA). Urine albumin-to-creatinine ratio (uACR) is recommended to identify patients with SCA-related CKD but its utility in predicting long-term kidney dysfunction remains unclear in this patient population. In two independent, longitudinal cohorts of patients with hemoglobin SS or Sβ0-thalassemia (USA: n = 268, median follow-up 6 years; France: n = 310, median follow-up 8.2 years) we investigated the utility of uACR, as well as other clinical and modifiable risk factors, for predicting a decline in kidney function as determined by the rate of estimated glomerular filtration rate (eGFR) decline. Using linear mixed-effects models, a higher baseline uACR independently predicted a faster rate of eGFR decline as well as a more rapid annual eGFR decline, defined as ≥ 3 mL/min/1.73m2 (p ≤ 0.009). Furthermore, baseline uACR of ≥ 100 mg/g creatinine was independently associated with the rate of eGFR decline and rapid annual eGFR decline in both cohorts. Tobacco smoking was also associated with a faster rate of eGFR decline and was congruous between the two cohorts. In conclusion, we demonstrate that uACR is an important clinical tool that predicts a more rapid decline in kidney function and should be routinely monitored in people with SCA. Our data also support preventative care to reduce tobacco smoking for mitigating the risk of CKD progression in this high-risk population.
    Keywords:  albuminuria; kidney; sickle cell disease; tobacco smoking
    DOI:  https://doi.org/10.1002/ajh.70155
  5. Hematology Am Soc Hematol Educ Program. 2025 Dec 05. 2025(1): 577-584
      Sickle cell disease (SCD) is a genetically and clinically heterogeneous disorder marked by hemolysis and vaso-occlusion, leading to a wide range of acute and chronic complications. While newborn screening enables early identification, the optimal timing for initiating disease-modifying therapies (DMTs) remains a critical and evolving question. This review explores how genetic and clinical risk factors, along with phenotypic variability, influence treatment timing, emphasizing a shift toward earlier and more personalized interventions. Hydroxyurea, the most widely used DMT, demonstrates strong evidence for early initiation in severe genotypes yet is underutilized due to concerns around long-term effects and adherence challenges. Additional therapies, such as L-glutamine, crizanlizumab, and formerly voxelotor, highlight the growing yet complex therapeutic landscape. Curative and transformative options, such as hematopoietic stem cell transplantation and newly approved gene therapies, underscore the need for individualized decision-making based on risk, disease trajectory, and patient goals. Rethinking treatment paradigms to incorporate multiagent approaches, biomarker-driven strategies, and earlier intervention may yield improved outcomes. Ultimately, optimizing the timing of therapy initiation requires moving from reactive to proactive care models that consider risk, clinical severity, and evolving therapeutic options, with the goal of improving quality of life and long-term survival for individuals living with SCD.
    DOI:  https://doi.org/10.1182/hematology.2025000752
  6. Hematology Am Soc Hematol Educ Program. 2025 Dec 05. 2025(1): 571-576
      Sickle cell disease (SCD), the most prevalent hemoglobinopathy globally, is a complex, systemic disorder with significant phenotypic variability and evolving clinical burden. As the therapeutic landscape expands-ranging from hydroxyurea and red blood cell transfusions to novel disease-modifying agents and curative approaches, such as hematopoietic stem cell transplantation and gene therapy-patient selection for each strategy becomes increasingly multifaceted. This article explores how clinical severity, genotype, age, organ involvement, access to care, and patient preferences interact in shaping therapeutic decisions. Two illustrative cases highlight how disease trajectory, individual choices, and real-world barriers influence eligibility and response to treatment. We propose a multidimensional framework for patient selection, incorporating both clinical indicators and patient-centered outcomes. While monotherapy with a single disease-modifying therapy remains the cornerstone of SCD treatment, all therapeutic decisions should be individualized. However, combination and curative approaches are more complex and require a comprehensive evaluation of efficacy, feasibility, and patient values. Emerging trends, including biomarker-driven stratification, inclusive clinical trials, and shared decision-making tools, coupled with the use of artificial intelligence, offer opportunities to better align therapy with the needs of diverse patients across settings. Ultimately, defining the "right" patient demands dynamic, context-sensitive evaluation, ensuring that therapeutic advances translate into equitable and valuable care for individuals with SCD globally.
    DOI:  https://doi.org/10.1182/hematology.2025000751
  7. Hematology Am Soc Hematol Educ Program. 2025 Dec 05. 2025(1): 585-591
      Sickle cell disease (SCD) remains the most common monogenic disorder worldwide, yet more than a century after its formal discovery, our treatment options and approach to care remain underdeveloped. Despite scientific progress, care for SCD continues to lag behind other chronic conditions, in part due to a lack of consensus on straightforward medical decision-making-driven by a persistent paucity of data and compounded by historical neglect, systemic inequities, and clinical heterogeneity. To truly serve this vulnerable population, we must move toward a more comprehensive, personalized approach to adult care-one that mirrors the individualized pain management plans routinely used in acute care settings. While much of the foundational work in SCD has been in pediatrics, this manuscript focuses on the adult population, where the burden of disease increases and access to specialized care declines. We emphasize the importance of considering genotype, hematologic profile, comorbid conditions, psychosocial context, and health literacy when developing treatment plans in shared decision-making with our patients. Ultimately, we hope this manuscript provides practical insights to help clinicians answer the daily complex questions surrounding sickle cell care: whom to treat and which interventions offer the most meaningful benefit for that particular patient.
    DOI:  https://doi.org/10.1182/hematology.2025000753