Dial M for HeMolysis

Abstract

A woman with sickle cell disease and multiple historical red cell antibodies received several red cell units in preparation for surgery. The laboratory did not select M-negative units for transfusion, assuming that the anti-M, one of the historical antibodies, is a cold-reacting antibody. A delayed hemolytic reaction due to an anti-M ensued. Causes of alloimmunization to red cell antigens, common in sickle cell disease, are discussed; characteristics of delayed hemolytic transfusion reactions in sickle cell disease are outlined. In its most severe form, hemolysis affects autologous red cells, a phenomenon called “sickle cell hemolytic transfusion reaction syndrome,” or “hyperhemolysis.”