Successful Medical Treatment of Hyperinsulinemic Hypoglycemia in the Adult: A Case Report and Brief Literature Review

Hyperinsulinemic hypoglycemia is characterized by inappropriate insulin secretion from the pancreatic beta cells causing low blood glucose levels. Nesidioblastosis is a very rare cause of hyperinsulinemic hypoglycemia in adults. Medical therapy can effectively improve disease symptoms. In 2014, a 45-year-old man presented with recurrent severe fasting and postprandial symptomatic hypoglycemia. The symptoms resolved after glucose ingestion. Fasting test was positive after only 4 h but imaging methods (abdominal computerized tomography, magnetic resonance imaging, endoscopic ultrasonography and octreotide scintigraphy) failed to identify pancreatic lesions. Hypoglycemia in face of endogenous hypetinsulinemia and lack of focal lesions in the pancreas in multiple imaging exams suggested the diagnosis of adult nesidioblastosis. The patient preferred conservative medical treatment in association with dietary recommendations. Nifedipine (30 mg/day) did not improve the glycemic profile and was poorly tolerated by the patient. Diazoxide 150 mg/day was started, with progressive increase to 400 mg/day over 6 weeks. Patient has been successfully treated with medical treatment for 5 years, with no events of severe hypoglycemia, no significant side effects and with marked improvement in quality of life. This clinical case demonstrates that adult hyperinsulinemic hypoglycemia can be effectively controlled with medical treatment, which is a viable alternative to pancreatic surgery.