Idiopathic postprandial hyperinsulinaemic hypoglycaemia.

Abstract

Idiopathic postprandial hyperinsulinaemic hypoglycaemia (PPHH) has rarely been reported in the paediatric age. The objective of this study was to describe the clinical characteristics, diagnosis and management in a group of children with PPHH. Six children (three females) with a mean follow-up of 3.5±3.0 years at a single tertiary paediatric hospital. All had 24-h blood glucose monitoring, diagnostic fast and prolonged oral glucose tolerance test (OGTT). Follow-up included: 24-h blood glucose monitoring or continuous glucose monitoring system, prolonged OGTT and/or mixed meal (MM) test. Age at diagnosis ranged from 5.4 to 15.7 years and auxology parameters were within normal range in all subjects. All the children had a normal fasting tolerance for age. Prolonged OGTT demonstrated symptomatic hypoglycaemia after 120 min in all the patients with simultaneous detectable serum insulin concentration. Acarbose was tried in three patients, having a positive effect on glycaemic and symptom control, but due to side effects, only two patients continued acarbose in the long run. Diazoxide proved to be beneficial in one patient. The rest of the patients were managed with frequent feeds but despite this, prolonged OGTT/MM demonstrated on-going PPHH. Prolonged OGTT is necessary to diagnose PPHH in children. Acarbose is beneficial in children with PPHH, although not well tolerated. Patients managed exclusively on frequent feeds demonstrated persistent hypoglycaemia on OGTT. The underlying cause of the PPHH in these patients remains unknown.