Alloimmunization in autoimmune hemolytic anemia patient: The differential adsorption approach

Patients of β-thalassemia major are dependent on regular blood transfusions for their entire lifetime. Development of antibodies against red blood cell (RBC) antigen which may be alloantibody or autoantibody, several times as a result of frequent red cell component transfusions, further complicates the subsequent transfusion therapy. Among the autoantibodies, warm-reactive autoantibodies are commoner and interfere in the pretransfusion testing. These RBC autoantibodies present in patient's serum potentially react with all the cells of antibody identification panel giving "pan-reactive" picture and making alloantibody identification complex. In this report, we present our approach in a thalassemia patient who presented with warm-type autoimmune hemolytic anemia, low hemoglobin of 5.8 g/dl, and three significant alloantibodies (anti-D, anti-S, and anti-Jk^b) which were masked by pan-reactive warm autoantibody(s). Differential adsorption was used to unmask underlying alloantibodies. We suggest that differential adsorption procedure is an effective and efficient method for autoantibody adsorption, detection, and identification of masked alloantibody(s), especially in patients with low hemoglobin and history of recent blood transfusion.