Successful subcutaneous glucagon use for persistent hypoglycaemia in congenital hyperinsulinism

Abstract Congenital hyperinsulinism (CHI) results from inappropriate excessive insulin secretion by the beta cells in the pancreas. A wide clinical spectrum of disease exists and a genetic diagnosis is now possible for approximately 50% of affected children. We describe a patient with atypical diffuse CHI caused by mosaic ABCC8 mutation inheritance, unmasked by paternal uniparental disomy. Hypoglycaemia persisted despite two subtotal pancreatectomies and trials of diazoxide and nifedipine were unsuccessful. Octreotide resulted in anaphylaxis, precluding its use. Continuous subcutaneous glucagon infusion was successful in restoring normoglycaemia and attenuating weight gain, with concomitant improvement of developmental milestones. No adverse effects have been encountered after >12 months of therapy. Administration problems (e.g., line crystallisation) may complicate continuous glucagon therapy; hence a practical description of infusion constitution is included. We recommend consideration of continuous subcutaneous glucagon infusion as a therapeutic option for persistent refractory hypoglycaemia in CHI.