Clinical Prevalence and Dominant Patterns of alloimmunization in Transfusion- Dependent Thalassemia Patients at Ahvaz Shafa Hospital

Background and objective: Thalassemia patients require regular blood transfusions due to the nature of their disease. Alloantibody (ies) cause delayed hemolysis leading to increased need for blood and to intensified complications resulting from frequent transfusions in these patients. This study was conducted to determine alloimmunization prevalence among the study group and to identify the dominant alloantibody (ies) pattern. Methodology: This cross-sectional study was carried out on 133 transfusion-dependent thalassemia patients at Ahvaz Shafa Hospital, Standard antibody sampler kits produced by the Iranian Blood Transfusion Organization were employed to determine types of alloimmunization in patients to red blood cell antigens using the test tube method. Results : Of the 133 patients in the study, 66 (49.1) were males and 67 (50.9%) females, with the age range of 2-54 and mean age of 17.63±7.6 years. Screening tests were positive in 42 (31.57%) of the patients, 25 (59.52%) of whom had alloantibody (ies) and 17 (40.5%) autoantibody. The dominant alloimmunization types in the study were antibody against Rh subgroups (55%) and against Kell groups (33%). Alloimmunization had a significant relationship with increased age at the start of blood transfusions, with the removal of the spleen, and with the type of thalassemia. Conclusions: The high prevalence of alloimmunization in the study population showed the need for determining blood subgroup types, especially Rh and Kell subgroups, in thalassemia patients before starting treatment with blood transfusion, and for preparing bloods compatible with the blood subgroups with the purpose of reducing delayed immune responses.