Clinical features of 52 neonates with hyperinsulinism

Background Neonatal hyperinsulinemic hypoglycemia is often resistant to med ical therapy and is often treated with near-total pancreatectomy. However, the pancreatic lesions may be focal and treatable by partial pancreatic res ection. Methods We studied 52 neonates with hyperinsulinism who were treated surgic ally. The type and location of the pancreatic lesions were determined by pr eoperative pancreatic catheterization and intraoperative histologic studies . Partial pancreatectomy was performed in infants with focal lesions, and n ear-total pancreatectomy was performed in those with diffuse lesions. The p ostoperative outcome was determined by measurements of plasma glucose and g lycosylated hemoglobin and by oral glucose-tolerance tests. Results Thirty neonates had diffuse beta-cell hyperfunction, and 22 had foc al adenomatous islet-cell hyperplasia. Among the latter, the lesions were i n the head of the pancreas in nine, the isthmus in three, the body in eight , and the tail in two. The clinical manifestations were similar in both gro ups. The infants with focal lesions had no symptoms of hypoglycemia and had normal preprandial and postprandial plasma glucose and glycosylated hemogl obin values and normal results on oral glucose-tolerance tests after partia l pancreatectomy (performed in 19 of 22 neonates). By contrast, after near- total pancreatectomy, 13 of the patients with diffuse lesions had persisten t hypoglycemia, type 1 diabetes mellitus developed in 8, and hyperglycemia developed in another 7; overall, only 2 patients with diffuse lesions had n ormal plasma glucose concentrations in the first year after surgery. Conclusions Among neonates with hyperinsulinism, about half may have focal islet-cell hyperplasia that can be treated with partial pancreatectomy. The se neonates can be identified through pancreatic catheterization and intrao perative histologic studies. (N Engl J Med 1999;340:1169-75,) (C)1999, Mass achusetts Medical Society.