Management and short-term outcome of persistent hyperinsulinaemic hypoglycaemia of infancy (nesidioblastosis)

Persistent hyperinsulinaemic hypoglycaemia is a rare metabolic disorder of glucose regulation. It is however the most common cause of persistent hypoglycaemia in the neonatal period. Various drugs have been used with generally poor results, but diazoxide and a long-acting somatostatin analogue, octreotide, have been found to be rather successful. When medical therapy fails, early pancreatectomy is recommended to maintain euglycaemia. Since pancreatectomy seems to carry the long-term risk of diabetes mellitus, some authors recommend long-term medical therapy as an alternative to surgery. The outcome of treatment seems to correlate with neurological status prior to surgery. Even in early recognised and treated patients, publications suggest that a subtle neurological deficit may be present despite apparently normal intelligence. In view of the varying recommendations on treatment and the variations in outcome, we reviewed our experience over a period of three years (1992-1995) to determine whether we could formulate a rational approach to the management.

From our records, we identified 8 children who fullfilled the criteria for the diagnosis of persistent hyperinsulinaemic hypoglycaemia of infancy and retrospectively reviewed their documents. We also included 2 more who presented to us during the study period.

Two out of the 10 were born premature and four were considered large for gestational age, mean birth weight was 3679 gms (range 2580-4400 gms). All except three were symptomatic by day two of life. All except one were given hydrocortisone prior to transfer to our care at a mean age of 22 days (range 8-52 days). Our regime included a trial of diazoxide and octreotide. Near total pancreatectomy was performed in nine patients, seven following a short trial of octreotide. Our two most recent cases were given a longer trial of medical therapy of 9 and 6 months respectively prior to pancreatectomy. Our two early cases in the series had recurrence of hypoglycaemia within a week post-pancreatectomy. One still needed insulin therapy 5 months post-surgery. Seven were available for outcome assessment; while longitudinal growth is normal in all, three were developmentally delayed.

Based on our experience with short and prolonged course of somatostation analogue, we conclude that early pancreatectomy should be performed on those with inadequate maintenance of euglycaemia while prolonged course of medical therapy is feasible only in selected cases.