Alloimmunization and Erythrocyte Autoimmunization in Transfusion-dependent Egyptian Thalassemic Patients

Abstract

Background Alloimmunization to red blood cells' (RBCs) antigens and formation of autoantibodies against RBCs is a frequent complication among immunocompetent transfusion-dependent patients. Autoantibodies can result in clinical hemolysis and difficulty in cross-matching blood. The objective of this study was to evaluate the presence of alloantibodies and autoantibodies in regularly transfused β-thalassemic patients and the factors influencing the development of alloantibodies. Materials and Methods The clinical and transfusion records of 95 Egyptian β-thalassemic patients, with a mean age of 17.07 years, presenting to the National Blood Transfusion Centre for regular blood transfusion were evaluated for alloimmunization and antibody formation. Results Alloantibodies were encountered in 27 patients (28.4%). The most frequent alloantibodies encountered were anti-Kell (23.6%) and anti-E (23.6%). Patients with blood group O were the highest in developing antibodies (37.9%). Patients with blood phenotypes R2r Kell negative developed more alloantibodies. Autoantibodies were encountered in only 1 patient. Conclusions Alloimmunization to RBCs' antigens is a frequent finding among Egyptian transfusion-dependent thalassemic patients, with the majority of patients being transfused with blood matched for ABO and D antigens only. Absence of phenotypically matched donors, except for a limited number of patients, may have contributed to this problem.