ESPE Abstracts

Congenital hyperinsulinism is a rare genetic cause of symptomatic hypoglycemia carrying risk of significant morbidity and mortality if left undiagnosed and untreated. It is characterized by unregulated insulin secretion from pancreatic beta cells leading to hypoglycemia. It can be broadly classified into diffuse and focal types. Till date, at least nine different types of genes are identified among which ABCC8 and KCNJ11 are the most common genetic mutations. Genetic mutation can either be inherited as autosomal recessive or autosomal dominant forms. We present series of 3 challenging cases of congenital hyperinsulinism that presented to our pediatric endocrine department at NICH.

Case 1: 25 days old neonate with very sick early neonatal course requiring ventilatory support presented to us with respiratory distress and persistent hypoglycemia. Critical sampling at the time of hypoglycemia revealed endogenous hyperinsulinism. Genetic analysis revealed two pathogenic variants in ABCC8 gene associated with autosomal recessive and autosomal dominant forms of permanent neonatal diabetes and congenital hyperinsulinism. Baby was managed medically with intravenous fluids for maintaining GIR initially then was discharged on fantomalt milk cap dizoxide for managing hypoglycemic episodes after stabilization

Case 2: 2 months old female child presented with symptoms of persistent hypoglycemia. Her critical sampling at the time of hypoglycemia revealed evidence of endogenous non ketotic hypoglycemia. Whole genomic studies showed evidence of pathogenic variants of ABCC8 gene mutations associated with persistent diabetes mellitus and congenital hyperinsulism. She was also managed medically after initial stabilization at pediatric endocrine department of NICH with fantomalt milk capsule diazoxide and injection octeriotide

Case 3: 3 months old female child presented with symptomatic hypoglycemic episodes and respiratory distress. Her critical sampling also revealed endogenous non ketotic hypoglycemia. She was diagnosed using DOPA-PET scan showing findings consistent with diffuse congenital hyperinsulinism. This child was also managed medically with fantomalt milk and cap diazoxide. Later on injection octertide was given but still situation was not improved so ultimately patient underwent subtotal pancreatomy. Her genetic workup was negative.

Conclusion: Congenital hyperinsulinism is a medically challenging disorder which if timely diagnosed and treated can prevent neurological impairment and morbidity associated with persistent hypoglycemia. It is managed medically using nutritional supplements and diazoxide (potassium channel activator) with subtotal pancreatectomy as the last option.