Renal graft rejection after allogeneic peripheral-blood stem cell transplantation.

A 28-year-old woman underwent peripheral-blood stem cell transplantation from her HLA-identical sister for cytogenetic progression of Fanconi anemia. She had received a living-related renal allograft from her father 2 years previously. Nine days after peripheral-blood stem cell transplantation, she developed acute renal failure secondary to acute rejection. Severe microangiopathic hemolysis developed, and cyclosporine therapy was discontinued. Renal biopsy showed humoral rejection and thrombotic microangiopathy. Despite daily plasmapheresis and immunosuppression, she remained dialysis dependent. The renal graft was removed, with rapid resolution of microangiopathic hemolysis. At no stage was there evidence of acute graft-versus-host disease. We speculate that the engrafting third-party hematopoiesis produced acute renal allograft rejection with secondary microangiopathic hemolysis through a graft-versus-graft mechanism.