Hyperinsulinism presenting in childhood and treatment by conservative pancreatectomy.

OBJECTIVE: To describe the uncommon presentation of hyperinsulinism in an 8-year-old boy.
METHODS: We describe the patient's clinical findings, results from biochemical and imaging studies, surgical approach, and outcome. The discussion encompasses a review of literature that provided the basis for the diagnostic and surgical approach applied to this patient's case.
RESULTS: An obese 8.5-year-old boy initially presented with hypoglycemic seizures after initiation of dietary changes to treat obesity. Biochemical analysis indicated hyperinsulinism. Endoscopic ultrasonography showed no pancreatic lesions suggestive of insulinoma. Genetic studies identified no known mutations in the ABCC8, KCNJ11, GCK, or GLUD1 genes. Selective arterial calcium stimulation and hepatic venous sampling did not document a focal source for hyperinsulinism in the pancreas, and positron emission tomography with 18-fluoro-L-3,4-dihydroxyphenylalanine showed diffusely increased uptake in the pancreas. The patient ultimately required partial pancreatectomy because of continued hypoglycemia while taking diazoxide and octreotide. Intraoperative glucose monitoring directed the extent of surgical resection. A 45% pancreatectomy was performed, which resolved the hypoglycemia but led to impaired glucose tolerance after surgery.
CONCLUSION: The unusual presentation of hyperinsulinism in childhood required a personalized approach to diagnosis and surgical management using intraoperative glucose monitoring that resulted in a conservative pancreatectomy.