CASE REPORT Anti-S Alloantibody Underlying Pan Agglutinating Autoantibody in a Patient of Systemic Lupus Erythematosus

Autoimmune haemolytic anaemia (AIHA) is seen in about 13% of Systemic Lupus erythematosus (SLE) cases (1). Autoantibodies make transfusion management of these patients very difficult. Some of these patients have associated underlying alloantibodies which get masked due to pan agglutinating nature of autoantibodies. Furthermore, difficulties are encountered in grouping, cross matching and selection of appropriate blood for transfusion in these patients. Pan agglutinating nature of autoantibodies causes incompatibility with all the donor units selected for transfusion. In such cases, the least incompatible blood may be transfused, if required (2). Presence of underlying alloantibodies, if not detected, will increase the haemolysis of the transfused red cells. Also the titres of alloantibodies increase with subsequent transfusions. Hence, it is imperative that extensive immunohematological workup be done to identify the nature of autoantibodies (if possible) and alloantibodies, including their thermal amplitude, titres and specificities. Here we present a case of underlying anti-S alloantibody along with autoantibody in a case of SLE.