Red blood cell alloimmunization in transfusion-dependent β-thalassemia major patients in Eastern Iran

Patients with thalassemia major require regular blood transfusions, which cause complications such as iron overload, increased risk of blood-borne diseases, and production of alloantibodies against donor blood cells. This study aimed to investigate the prevalence and types of alloantibodies in patients with transfusion-dependent thalassemia. This cross-sectional study was conducted on 74 transfusion-dependent thalassemia patients in southern Khorasan Province, Iran. The patients’ ABO and Rh blood groups phenotyping was determined. Serum samples from all patients underwent initial antibody screening, followed by antibody identification in samples that tested positive. Demographic information of patients was extracted from their electronic records. This study included 37 males and 37 females, 50% each, aged 1–37 years old. Antibody screening was positive in 7 patients (9.5%). 16 alloantibodies were identified. The most prevalent alloantibodies were anti-K (43.75%) and anti-E (43.75%), followed by anti-C (12.5%). Within the ABO system, blood group O was the most frequent phenotype (39.2%), while in the Rh system, antigens C and E were the most common, present in 94.6% of participants. Statistical analysis revealed no significant association between alloimmunization and demographic data such as age, sex, blood group, hemoglobin levels, number of blood units transfused and splenic status. Our results show that alloimmunization is still a chronic problem in our transfusion-dependent thalassemia group, despite the recognized benefits of antigen-matched transfusions. These results reinforce the necessity of using regionally specific approaches to improve transfusion safety, such as expanded donor phenotyping and regular antibody screening.