Transfusion-induced alloimmunization in patients awaiting renal allografts

Lymphocytotoxic antibodies can be induced by the immunologic stimulus of pregnancy, blood transfusion, or tissue allograft. The presence of such antibodies can delay or prevent renal transplantation. However, a history of prior transfusion exposure has been strongly associated with excellent renal allograft survival. The problem of ensuring this 'transfusion effect' while minimizing the risk of alloimmunization is real for patients awaiting renal allografts. We examined the influence of pregnancy, allograft rejection, and transfusions on the levels of lymphocytotoxic antibodies in the sera of patients awaiting renal transplantation. The results indicate that transfusions alone have a minimal effect on alloimmunization in men and in nulliparous women. The influence of transfusions alone was seen in 77% of men and 86% of women showing less than 10% panel reactivity. Deliberate transfusion policies for patients awaiting renal allografts should be designed to minimize transfusion exposure to parous patients or those who have previously rejected a renal graft.