Hypoglycemia Following Pancreas Transplant: A Diagnostic Challenge in the Immediate Posttransplant Setting

Few studies have described glucose metabolism in the immediate posttransplant period. Here, we report a 37-year-old female patient who had transient hypoglycemia after combined pancreas and kidney transplant for poorly controlled type 1 diabetes and renal failure. Although the patient's blood sugar decreased from 420 to less than 120 mg/dL and the kidney demonstrated graft function immediately posttransplant, at 19 hours after transplant, the patient's blood glucose decreased to below the normal range at a nadir of 59 mg/dL. When treated with intravenous dextrose, her blood glucose levels increased over 7 hours to 119 mg/dL but then again declined, appearing to follow a circadian rhythm, with hypoglycemia shown during early morning hours and then improving during the afternoon. This prompted treatment with a continuous infusion of 5% dextrose on day 2, resulting in blood sugar levels returning to normal by day 4 and discharge on day 6. She has since remained euglycemic. The differential diagnosis of hypoglycemia immediately after kidney-pancreas transplant is wide. Indeed, after we excluded ischemia-reperfusion injury, impaired renal clearance, insulin-associated antibodies, and lack of pancreatic innervation, we believe that cause was most likely due to impairment of early glucose counterregulatory responses or delayed alpha cell function.