Hemolytic uremic syndrome in small-bowel transplant recipients: the first two case reports

Post-transplant hemolytic uremic syndrome (HUS) is an uncommon but well-des cribed complication in solid organ transplant recipients. Believed to be se condary to immunosuppressive therapy, it has been reported after kidney, li ver, pancreas, heart, and lung transplants. In all reported cases, the prim ary organ affected was the kidney (transplant or native). But until, now, n o cases after small-bowel transplants and no cases in which the kidney was not the primary ore;an affected have been reported. We report two cases of HUS in small-bowel transplant recipients. In our first case, clinical prese ntation was with renal failure; biopsy of the native kidney demonstrated th e typical histological changes seen with HUS, namely occlusion of the micro circulation by thrombi and platelet aggregation. Immunosuppression was chan ged from tacrolimus to cyclosporin, but with no improvement in renal functi on. In our second case, the transplanted bowel was the primary organ affect ed. This recipient presented with ulcers in the bowel mucosa, which were be lieved to be ischemic in origin, secondary to occlusive vascular lesions af fecting the small vessels in the transplanted bowel. Her tacrolimus dose wa s decreased with resolution of ulcers and no evidence of rejection. These t wo cases represent the first reports of HUS after small-bowel transplants; in addition, our second case represents the first report of an extrarenal g raft as the primary organ affected. When caring for small-bowel transplant recipients, physicians must be alert to the possibility of HUS and its vari ous presentations.