Antibody-mediated hemolytic anemia following ABO-mismatched organ transplantation: contributory role of HLA matching and polyclonal antilymphocyte globulin.

We report three instances of antibody-mediated hemolytic anemia following ABO-mismatched, but compatible, renal (n = 2) and simultaneous pancreas-kidney (n = 1) transplantation. The two renal allograft recipients had received a 6-antigen matched transplant; one received polyclonal antilymphocyte globulin to treat an early rejection episode. The simultaneous pancreas-kidney transplant received polyclonal antilymphocyte globulin (ALG) as part of a quadruple therapy induction regimen. All three patients developed severe, but self-limited, antibody-mediated hemolytic anemia within two weeks of their transplants. Serologic testing demonstrated the hemolysis to be antibody mediated; furthermore, testing of the ALG lots demonstrated high titers of anti-red blood cell antibodies. The possible contribution of ALG and HLA matching to the hemolysis seen in these patients after ABO mismatched organ transplantation is discussed.