A case of Fabry's disease in a renal transplant recipient with a follow-up period of 11 years is reported. The patient suffered from renal, skin, peripheral nerve lesions, and asymptomatic cardiomegaly. Fabry's disease symptoms disappeared after transplantation. Improvement of renal function was rapidly observed, and it remained satisfactory during the whole posttransplantation period. The patient died of a severe, uncontrolled infection and of biliary peritonitis. Autopsy showed a polyvisceral accumulation of sphingolipids deposits. The engrafted kidney was histologically free of disease. Ultrastructurally, it revealed numerous sphingolipid inclusions in the endothelial cells of capillaries. The explanation of this complication could be attributed to: (1) high circulating levels of plasma substrates locally overwhelming the enzymatic capability of the graft endothelial cells; and (2) the endothelial cells originated from the recipient but not from the donor, an occurrence that has been described after transplantation. Rejection and the newly formed deposits in the endothelial cells may lead to the loss of the engrafted organ. As a consequence of the increasing possibility of organ transplantation, this complication should be detected by studying the blood vessels ultrastructurally in order to evaluate the condition of the transplant.