Islet Transplantation at the University of Alberta: Status Update and Review of Progress over the Last Decade

The general perception of islet transplantation among the diabetes community is somewhat negative, as insulin independence was maintained in only a small minority and there are fears about the safety of lifelong immunosuppression. There has been substantial progress in refining the islet transplant procedure to enhance its safety, reduce the toxicity of immunosuppression and improve long-term graft function. Longer-term follow-up studies have clarified the indications for islet transplantation; frequent, severe hypoglycemia, hypoglycemia unawareness and glycemic lability; facilitated informed consent and provided a framework for more realistic expectations, and suggest beneficial effects on microvascular complications. One hundred thirty-eight individuals have undergone islet transplantation at the University of Alberta over the last 12 years. Of these, 109 (79%) have full or partial graft function. Patient survival is 96% with no deaths due to transplantation. Three subjects have been hospitalized because of severe opportunistic infection and 3 have progressed to require renal replacement therapy. Current protocols are able to achieve insulin independence rates of 60% beyond 4 years. Safer and more effective islet transplantation, along with refinements in immunosuppressive therapy, make islet transplantation a more attractive option for a subset of persons with type 1 diabetes who suffer from frequent, severe hypoglycemia, lability and/or hypoglycemia unawareness, and resulting in excellent glycemic control and freedom from hypoglycemia. (C) 2012 Canadian Diabetes Association