RBC alloimmunization and autoimmunization among transfusion-dependent Arab thalassemia patients

Thalassemia major is a common hemoglobinopathy in the Arabian Gulf region. However, limited data are available on the frequency of RBC alloimmunization and autoimmunization in transfusion-dependent Arab thalassemia patients.

A total of 190 thalassemia major patients were classified as Kuwaiti Arab and non-Kuwaiti Arab. Pretransfusion investigation records were reviewed for the presence of RBC alloantibody and autoantibody, and the age at which RBC alloantibody was developed.

Fifty-seven (30%) patients developed RBC alloantibodies. The most common clinically significant alloantibodies were directed against antigens in the Kell and Rh systems. Anti-K developed in 41 (72%) patients followed by anti-E in 26 (45.6%). RBC autoantibodies developed in 21 (11%) patients with and without underlying RBC alloantibodies. Sixty-six (49.6%) RBC alloantibodies developed between the ages of 2 and 10 years.

Several factors might have contributed to the high alloimmunization and autoimmunization rate observed in this study, including the heterogeneity of the population living in Kuwait, lack of better-matched donors for those patients, and the use of poststorage leukodepleted blood. It is recommended that thalassemia patients receive blood matched for Rh and Kell antigens and prestorage leukodepleted RBCs.