Persistent hyperinsulinaemic hypoglycaemia of infancy: case report.

Hyperinsulinism, although rare, is the most common cause of persistent hyperinsulinaemic hypoglycaemia in infancy. Because of persistent hypoglycaemia, serious difficulties are encountered in the long term management of this condition. A male neonate, after an uncomplicated full-term pregnancy, had been admitted to another hospital with convulsions on the third post-natal day. Meningitis had been suspected at that time and treated with phenobarbital and he had been discharged from the hospital. At three-months old he was referred to our department for persistent convulsions and lethargy. His parents were of 1st degree consanguinity. His blood glucose level was found to be 24 mg/dl (1.33 mmol/L). Because of the dangerously high insulin level during hypoglycaemia (insulin/glucose > 0.3), the absence of ketonuria, and the need for a high dose of glucose infusion (> 15 mg/kg/min) to achieve normoglycaemia and a glycaemic response to glucagon despite the hypoglycaemia, a diagnosis of persistent hyperinsulinaemic hypoglycaemia of infancy was made. Since maximal doses of prednisone, glucagon, diazoxide, octreotide and high infusion of glucose were ineffective in achieving normoglycaemia, a subtotal (80%) pancreatectomy was done. Postoperatively intermittent hypoglycaemic episodes continued. These were controlled with low doses of octreotide. Histology revealed diffuse adenomatous hyperplasia (nesidoblastosis). The boy is now in the sixth post-operative month and developing normally.