A Congenital Anemia Reveals Distinct Targeting Mechanisms for Master Transcription Factor GATA1

Master regulators, such as the hematopoietic transcription factor (TF) GATA1, play an essential role in orchestrating lineage commitment and differentiation. However, the precise mechanisms by which such TFs regulate transcription through interactions with specific cis-regulatory elements remain incompletely understood. Here, we describe a form of congenital hemolytic anemia caused by missense mutations in an intrinsically disordered region of GATA1, with a poorly understood role in transcriptional regulation. Through integrative functional approaches, we demonstrate that these mutations perturb GATA1 transcriptional activity by partially impairing nuclear localization and selectively altering precise chromatin occupancy by GATA1. These alterations in chromatin occupancy and concordant chromatin accessibility changes alter faithful gene expression, with failure to both effectively silence and activate select genes necessary for effective terminal red cell production. We demonstrate how disease-causing mutations can reveal regulatory mechanisms that enable the faithful genomic targeting of master TFs during cellular differentiation.

A Case Study in Process Improvement to Minimize Delays from Obtaining Blood for Red Cell Exchange for a Patient with Sickle Cell Disease and Multiple Red Blood Cell Alloantibodies

The process of procuring several units of red blood cells for red cell exchange can sometimes take several hours to days, especially for patients with multiple clinically significant red cell alloantibodies. This can introduce delays, inconveniences, and even health challenges for the patient. For most planned exchanges, these delays are preventable with some foresight and process modifications that are relatively minor yet high leverage. We report a case study of process improvement whereby the apheresis nurse sends an e-mail to the blood bank when the nurse makes the patient’s next red cell exchange appointment as the signal to order blood about 6–8 weeks before the exchange.

Prevalence and aetiologies of anaemia among first trimester pregnant women in Sri Lanka; the need for revisiting the current control strategies

Background The Sustainable development goals, which focus strongly on equity, aim to end all forms of malnutrition by 2030. However, a significant cause of intergenerational transfer of malnutrition, anaemia in pregnancy, is still a challenge. It is especially so in the low- and middle-income settings where possible context-specific aetiologies leading to anaemia have been poorly explored. This study explores the prevalence of etiological factors significantly contributing to anaemia in pregnancy in Sri Lanka, a lower-middle-income country with a high prevalence of malnutrition albeit robust public health infrastructure. Methods All first-trimester pregnant women registered in the public maternal care programme in the Anuradhapura district from July to September 2019 were invited to participate in Rajarata Pregnancy Cohort (RaPCo). After a full blood count analysis, high-performance liquid chromatography, peripheral blood film examination, serum B12 and folate levels were performed in anaemic participants, guided by an algorithm based on the red cell indices in the full blood count. In addition, serum ferritin was tested in a random subsample of 213 participants. Anaemic women in this subsample underwent B12 and folate testing. Results Among 3127 participants, 14.4% (95%CI 13.2–15.7, n = 451) were anaemic. Haemoglobin ranged between 7.4 to 19.6 g/dl. 331(10.6%) had mild anaemia. Haemoglobin ≥13 g/dl was observed in 39(12.7%). Microcytic, normochromic-normocytic, hypochromic-normocytic and macrocytic anaemia was observed in 243(54%), 114(25.3%), 80(17.8%) and two (0.4%) of full blood counts in anaemic women, respectively. Microcytic anaemia with a red cell count ≥5 * 106 /μl demonstrated a 100% positive predictive value for minor haemoglobinopathies. Minor hemoglobinopathies were present in at least 23.3%(n = 105) of anaemic pregnant women. Prevalence of iron deficiency, B12 deficiency and Southeast Asian ovalocytosis among the anaemic was 41.9% (95%CI 26.4–59.2), 23.8% (95%CI 10.6–45.1) and 0.9% (95%CI 0.3–2.3%), respectively. Folate deficiency was not observed. Conclusion Even though iron deficiency remains the primary cause, minor hemoglobinopathies, B 12 deficiency and other aetiologies substantially contribute to anaemia in pregnancy in this study population. Public health interventions, including screening for minor hemoglobinopathies and multiple micronutrient supplementation in pregnancy, should be considered in the national programme for areas where these problems have been identified.

TRANSFUSION PRACTICE, POST-TRANSFUSION COMPLICATIONS AND RISK FACTORS IN SICKLE CELL DISEASE IN SENEGAL, WEST AFRICA.

Context and Objectives: Blood transfusions (BT) remain a mainstay of therapy for patients with sickle cell disease (SCD), but pose significant clinical challenges. We aim to assess infectious markers, red cell alloimmunization and iron overload secondary to BT in SCD patients. Materials and Methods: This is a case-control study included 253 SCD (153 SCD-transfused and 100 SCD non-transfused). We evaluated the transfusion practice (modalities, indications), post-transfusion complications (infections, alloimmunization, iron overload) and risk factors of these complications (socio-demographic, clinical, biological). Results: Median age was 28.5 years (5 - 59). Sex ratio was 0.86. Homozygous SCD was more common (95.3%). Simple BT was performed in 92.8% and transfusion exchange in 18.9%. Transfusion indications were dominated by acute anemia (57.06%) and vaso-occlusive crisis (VOCs) (14%). Red blood cell concentrates (RBC) were administered to 93.46%. Median number of RBC received per patient was 10 (2 - 48). The prevalence of VHC in SCD-transfused was 1.33% and 2% for VHB. Anti-HIV antibodies were not found. Red cell alloimmunization frequency was 16%. The most common alloantibodies were anti-rhesus (34.19%) and anti-Kell (23.67%). Iron overload was detected in 7.84%. The number of RBC transfused was the only risk factor for alloimmunization (p = 0.03) and iron overload (p = 0.023). BT frequency was not related to infectious transmission. Conclusion: Despite advances in blood safety, BT therapy is still a risk for SCD polytransfused patients. Although infectious transmission has rare, the risk of alloimmunization and iron overload is high in these patients.