Prevalence and Specificities of Immune Red Cell Antibodies in Adult Patients with Sickle Cell Anaemia and Blood Donors in Uyo, South-South Nigeria: A Case-Control Study

Abstract

Background: Sickle cell anaemia (SCA) is a major public health issue in Sub-Saharan Africa, including Nigeria. Transfusion of red blood cells is an essential therapeutic modality in SCA. Repeated RBC transfusions can cause alloimmunization resulting in haemolytic transfusion reactions, transfusion refractoriness among other complications. Aims and Objectives: The study aimed to determine the prevalence and specificities of immune erythrocyte alloantibodies among adult patients with SCA compared with healthy HbAA blood donors in Uyo, South-South Nigeria. Materials and Methods: All participants were interviewed using a structured questionnaire to obtain information on bio- data, blood transfusion history and other relevant SCA history. Antibody screening and identification were carried out using tube agglutination method with commercially made panel of cells. Results: A total of 160 subjects were studied. They were made up of 80 SCA patients and 80 healthy HbAA blood donors. Prevalence of red cell alloimmunization among multi-transfused patients with SCA was observed to be 11.3%. Alloantibodies identified were mainly against Rh antigens contributing 66.7% (anti-E 22.2%, anti-C 22.2%, anti-D 11.1% and anti-e 11.1%). Antibodies directed against Kell and Lutheran blood group antigens together constituted 33.3%. No antibody was detected in the controls. Advancing age (30 years and above) and ABO blood group were statistically associated with alloimmunization (P values of 0.043 and 0.013, respectively). Conclusion: Repeated blood transfusion is associated with the development of alloantibodies. Immunohaematologic tests in transfusion care of SCA patients should be improved to include extended red cell phenotyping and routine alloantibody screening and identification.