[End-stage nephropathy in type 1-diabetes mellitus - kidney transplantation alone or combined with islet or pancreas transplantation?].

Due to the recent changes in reimbursement politics in islet and pancreas transplantation in Switzerland, the question, which patients with type 1-diabetes mellitus get which form of beta-cell replacement, is of utmost importance for referring physicians. As of July 1, 2010 all forms of islet- or pancreas-transplantations are reimbursed by the Swiss health care system. The limited availability of donor organs and the necessity of transplantation of the islets of several pancreata in order to achieve insulin independence has led to a change in paradigms in Switzerland, where insulin independence by multiple islet transplantations is not the key goal in islet transplantation any longer. The primary goal is achieving a good blood glucose control and avoidance of severe hypoglycaemic episodes. This goal can be achieved in 80 - 90 % of all patients. Only if this goal cannot be achieved by a single islet transplantation, a second or third islet transplantation is performed. By adapting this strategy more patients can benefit from this new therapy. Unlike the North American centers, the Swiss centers in Zurich and Geneva concentrated their efforts on islet after kidney and simultaneous islet kidney transplantation. Due to the organ donor shortage in Switzerland, 50 % of kidney transplants are nowadays living-organ donations, therefore this option has to be included in the decision tree of a beta cell replacement. The choice between islet and pancreas transplantation depends on the existence of diabetes complications (because the perioperative risk is considerably higher in pancreas transplantation) and the potential benefit of a pancreas- or islet transplantation. The first question in the decision tree is, therefore, whether the patient with type 1-diabetes and severe renal failure is a potential candidate for simultaneous pancreas-islet transplantation. If the perioperative risk is considered to be too high, or if revascularisation procedures cannot be done before transplantation, the patient qualifies only for islet transplantation. If a living organ donation for the kidney is possible and the patient not yet on dialysis then the patient can be listed for simultaneous islet-kidney or pancreas-kidney-transplantation. If dialysis is imminent or already performed, a living-donor kidney should be transplanted with the option of a later islet- or pancreas after kidney transplantation. If the patient with type 1-diabetes mellitus is able to maintain a reasonable glycemic level, he would be a good candidate for islet transplantation. If the patient is willing to take the additional risk of complications associated with a pancreas transplant, was never able to maintain a good glycated haemoglobin, has an acceptable perioperative risk, and wishes to become insulin-independent, a simultaneous pancreas-kidney transplant would be recommended. If the kidney has already been transplanted previously, a pancreas- after kidney transplantation would be the procedure of choice. An islet or pancreas transplantation alone is reserved for the patient with type 1-diabetes with a good renal function and frequent life-threatening hypoglycemias, which have to be balanced against the risks of a life-long immunosuppression. In this review article the advantages, disadvantages, and current indications for both beta-cell replacement options in Switzerland are discussed in the light of the available evidence with the help of a new flow chart.