Pancreas and islet transplantation

Transplantation of either pancreas or islet tissue is the only available therapy for type I diabetes that establishes normoglycemia and restores physiologic insulin secretion. This restoration of eu-glycemia may, in turn, be associated with beneficial effects on secondary diabetic complications. Despite increasing success rates and the obvious benefits for carbohydrate metabolism and diabetic complications, pancreas and islet transplantation are not yet considered standard therapy for patients with diabetes. The limitations of pancreas and islet transplantation include the morbidity and mortality associated with the surgery, the need for lifelong immunosuppressive therapy, and the significant financial costs of the procedure. In contrast to these limitations, successful pancreas transplantation establishes sustained normoglycemia without the need for exogenous insulin, restores glucose-responsive insulin secretion and glucagon response to hypoglycemia, and improves quality of life. For pancreas transplantation to achieve the clinical acceptability of other forms of transplantation, clear advantages over exogenous insulin therapy must be demonstrated. This can only happen with the completion of well-controlled comparative studies that permit a clearer understanding of the benefits and risks of pancreas transplantation in the treatment of type I diabetic patients.