Endocrine Abstracts

Introduction: In congenital hyperinsulinism (CHI) hypoglycaemia results from a dysregulation of insulin secretion. We hypothesised that other pancreatic hormones may also be dysregulated in this condition.

Objectives: To proof the applicability of Luminex Multiplex method to measure pancreatic hormones (insulin, C-peptide, glucagon, amylin and PP) in the paediatric age. To elucidate the fasting response of these hormones in children with different forms of CHI.

Subjects and methods: 12 children (seven females) with ages between 11 days of life and 13 years had the plasma pancreatic hormones extracted at normoglycaemia and at hypoglycaemia (end of fast). The patients have different CHI aetiologies, histology types and different response to treatments. The hormones were analysed using multiplexing manner on 0.025 ml of plasma.

Results: The concentration of glucagon (mean±SDS) increases from 97±239 pg/ml at normoglycaemia to 103±260 pg/ml at hypoglycaemia (p0.21). Conversely, insulin decreases from 909±441 to 503±306 pg/ml (p0.004), respectively. Similarly, C-peptide descends from 1547±1013 to 806±366 pg/ml at normoglycaemia and hypoglycaemia, respectively (P 0.005). Amylin decreases from 35±22 to 21±9 pg/ml (P 0.014) whilst PP is almost unmodified: 84±106 pg/ml at normoglycaemia and 86±115 pg/ml at hypoglycaemia (P 0.65).

Conclusions: This assay demonstrates its suitability to determine pancreatic hormones in the paediatric age group. In children with CHI, glucagon’s response to hypoglycaemia is impaired. No previous reports have determined amylin concentrations in CHI, and this study indicates that it decreases during hypoglycaemia to avoid its anorectic effect, although interestingly PP’s concentrations remain stable despite hypoglycaemia.