Recurrent hyperinsulinemic hypoglycemia caused by an insulin-secreting insulinoma.

BACKGROUND: A 37-year-old woman presented to her local physician in 1995 for evaluation of episodes of neuroglycopenia, which manifested as visual distortion and withdrawal without response to verbal commands in the food-deprived state. A 72 h fast was positive for hypoglycemia and the patient was given diazoxide and prednisone, but hypoglycemia was not controlled. The patient underwent pancreatic exploration in 1997, but no insulinoma was found. She was referred to the Mayo Clinic in 1998 for further evaluation and treatment. Abdominal CT and transabdominal ultrasound revealed a 1 cm insulinoma in the uncinate process of the pancreas. The patient again underwent pancreatic exploration. The insulinoma was removed, but during enucleation the tumor fractured. Hypoglycemia recurred 6 months later. INVESTIGATIONS: Laboratory tests, transabdominal ultrasound CT of the pancreas, endoscopic ultrasonography, fine-needle aspiration, and pancreatic exploration. DIAGNOSIS: Recurrence of hyperinsulinemic hypoglycemia caused by fracture of an insulin-secreting insulinoma. MANAGEMENT: Surgical excision of the recurrent tumor.