Multicenter trial of one HLA-DR-matched or mismatched blood transfusion prior to cadaveric renal transplantation

Background. The beneficial effect of blood transfusions before cadaveric renal transplantation on allograft survival, although previously well documented, has become controversial in light of their adverse effects. Recently, it has been suggested that their clinical benefits are due to HLA-DR sharing between the blood donor and recipient. Methods. In this prospective study. 134 naive patients were randomly assigned to receive one unit of blood matched for one-HLA-DR antigen (N = 49). or one unit of mismatched blood (N = 48), or to remain untransfused (N = 47). Graft survival and acute rejection rate were analyzed in 106 cadaveric renal allograft recipients receiving the same immunosuppressive protocol. Results. Graft survival was similar in the three groups at one and five years: 91.7 and 80% in untransfused patients. 90.3 and 79.3% in patients transfused with one DR-antigen-matched unit, and 92.3 and 83.7% in patients transfused with HLA-mismatched blood. The difference in the incidence of six-month post-transplant acute rejections was not statistically significant in the three groups: 12 out of 36, 33.3% in nontransfused patients: 6 out of 31, 19.4% in patients transfused with one DR-matched blood: and 13 out of 39. 33.3% in patients transfused with mismatched blood. Conclusion. The results of our prospective randomized trial showed that in a population of naive patients, one transfusion mismatched or matched for one HLA-DR antigen given prior to renal transplantation had no significant effect on the incidence and severity of acute rejection, and did not influence overall long-term graft outcome. Considering the potentially deleterious adverse effects of blood transfusions, the costs, and the considerable logistical efforts required to select and type blood donors, such a procedure cannot be recommended in a routine practice for patients awaiting cadaveric kidney transplantation.