Immuno-Hematological Complications of Transfusion in Thalassemia Patients: First Report in the Marrakech Region (Morocco)

Abstract

Background/Objectives: Erythrocyte alloimmunization is a critical complication impacting the efficacy of transfusion therapy in patients with thalassemia. This study seeks to evaluate the prevalence, characterization, and determinants of erythrocyte alloimmunization in multi-transfused thalassemia patients in south of Morocco. Methods: A retrospective study was conducted at the Moroccan Blood and Blood Derivatives Agency in Marrakech (Morocco) over 2 years, from June 2022 to June 2024, including 89 patients with beta-thalassemia receiving regular transfusions. The clinical, demographic, and transfusion characteristics of patients who developed alloimmunization were compared with those of non-alloimmunized patients. Results: Analysis of 89 β-thalassemia patients in the Marrakech region, mostly young and suffering from major form (67%), shows a significant male predominance (p = 0.004) and a high frequency of blood group O+ (49.4%). Alloimmunization mainly affects major forms and males and is associated with frequent annual transfusions (over 12 per year), usually resulting in the use of 24 to 60 packed red blood cell units annually. Alloimmunized patients mostly present anti-K and anti-E antibodies, indicating the involvement of the Kell and Rh systems. The direct Coombs test was more often positive in these patients (21.4% vs. 7.9%, p < 0.01). Conclusions: The high prevalence of alloimmunization in thalassemia patients in the Marrakech region highlights the need for a rigorous and personalized transfusion strategy, including molecular genotyping and alternative therapies.