Frequency and Distribution of RBC Alloantibodies among Transfused Patients at Ndola Central Hospital, Zambia

Background And Objectives: Alloantibody formation against red blood cell (RBC) antigens is a common complication of transfusion therapy. The RBC antigens and their alloantibodies vary among different human populations and ethnic groups, and they do have a clinical significance for their adverse immunological reactions. The prevalence of RBC alloimmunization is hardly known in Zambia and hence the need to conduct this study whose main aim was to determine the frequency and distribution of RBC alloantibodies at the Blood Transfusion Unit of Ndola Central Hospital.Materials And Methods: Using a cross-sectional design, transfused patients at Ndola Central Hospital in Zambia were investigated. Demographic characteristics and transfusion histories were recorded. EDTA blood samples were obtained from the hospital blood bank and RBC alloimmunization was demonstrated using immunohaematological tests. Results: The overall prevalence of alloimmunization was 70 (7.0%). The majority of these had a single alloantibody 55(78.6%), whereas the remaining 15(21.4% ) had multiple antibodies. The anti-E antibody comprised the most common alloantibody 19(27.0%) followed by anti K antibodies. Gender, number of blood units and ABO group A were found to be risk factors of alloimmunization in transfused patients. Conclusions: The prevalence of RBC alloimmunization in transfused patients at NCH is high and is mainly associated with the number of donor exposures. Women with multiple pregnancies are especially at risk of alloimmunization. We recommend the introduction of pretransfusion antibody tests in donor and patient’s blood.