Hypoglycaemia following physical exercise in a patient with novel SLC16A1 variant.

This article focuses on a case of exercise-induced hyperinsulinaemic hypoglycaemia linked to a rare variant in the SLC16A1 gene, which encodes monocarboxylate transporter 1 (MCT-1). The 41-year-old patient experienced severe hypoglycaemia and a seizure following strenuous exercise, with genetic testing revealing a deletion in the promoter region of SLC16A1, potentially causing abnormal MCT-1 expression in pancreatic beta cells and inappropriate insulin release during anaerobic exercise. The study demonstrated that subcutaneous octreotide, a somatostatin receptor analogue, reduced hyperinsulinaemia and hypoglycaemia in a dose-dependent manner, suggesting its therapeutic potential. The case highlights the possibility that exercise-induced hyperinsulinism due to SLC16A1 variants may be under-recognized and can present later in adulthood with hypoglycaemic unawareness.