The systemic venous drainage of the graft causes elevated plasma levels of insulin, which is known to be a potent regulator of plasma lipoprotein metabolism. As a result, SPK recipients have a favorable lipid profile compared with IDDM patients with kidney transplants. Diabetic Nephropathy, Retinopathy, Neuropathy, and Vasculopathy A functioning pancreas transplant can prevent or reduce the nephropathy that eventually develops in diabetic patients with a kidney graft. A recent study of renal transplant biopsies indicated a significant decrease in recurrent diabetic nephropathy in the kidneys of SPK patients after two and a half years. In one study in which renal biopsy samples taken before and after PTA from nonuremic IDDM patients were compared with biopsy samples taken from persistently hyperglycemic IDDM patients who did not undergo PTA, no significant difference was found over five years.
Pancreas transplantation appears to have no effect on retinopathy.
Compared with diabetic patients who receive kidney transplants, diabetics who receive SPK transplants experience no beneficial influence on progression of advanced diabetic retinopathy. It appears that the so-called point of no return for the influence on proliferative changes in the retina has been passed by the time most patients undergo transplantation. Reestablishment of the euglycemic state by successful pancreas transplantation halts or reverses diabetic neuropathy. In patients with kidney transplants, the neuropathy initially improves with elimination of uremia but tends to worsen during longer follow-up. In patients who also receive pancreas transplants, motor and sensory neuropathy improves during longer follow-up, but there is little or no improvement in autonomic dysfunction.