[Severe hemolysis related to an association of erythrocyte allo- and autoantibodies in a thalassemia patients].

Alloimmunization to red cell antigens and haemolytic transfusion reactions may occur after red blood cell transfusion. We describe a case of life threatening postransfusion hyperhaemolysis in a beta thalassaemia patient. For many years, transfusion therapy was stopped but the patient developed a profound anaemia which required splenectomy. At that time, the serum contained a red cell alloantibody with anti-KN3 specificity. In vivo red cell survival studies were performed trying to determine the capacity of this antibody to cause red cell destruction. Unfortunately, these studies triggered again an intense haemolytic process explained by the appearance of red cell auto- and alloantibodies. This case underlines a possible link between the development of alloimmunization and the induction of potentially serious autoimmune haemolytic anaemia.