Post-bariatric hypoglycaemia is increasingly recognised, usually attributed to hyperinsulinaemic mechanisms driven by altered incretin physiology. When insulin and C-peptide are suppressed, however, clinicians need to reconsider counter-regulatory failure.

In this case report, Hakami et al. describe a young woman presenting several years after sleeve gastrectomy, with recurrent postprandial and fasting hypoglycaemia that proved non-insulin-mediated. Detailed biochemical evaluation during a supervised fast demonstrated ketotic hypoglycaemia with appropriate cortisol responses but inappropriately low growth hormone (GH) secretion. Profound reductions in insulin-like growth factor-1 (IGF-1) and IGF-binding protein-3, failure to respond to glucagon stimulation, and a normal pituitary magnetic resonance imaging scan confirmed severe adult GH deficiency. Crucially, recombinant human GH replacement led to complete resolution of hypoglycaemia and restoration of fasting tolerance.

Although adult GH deficiency rarely presents with hypoglycaemia, this report highlights how bariatric surgery may act as a metabolic stress test, unmasking previously compensated deficiencies. Profound weight loss, depleted hepatic glycogen reserves, enhanced insulin sensitivity and impaired lipolysis together remove key glucose-buffering mechanisms. For endocrinologists, this paper reframes a paediatric concept in a post-bariatric context, and encourages broader evaluation of counter-regulatory failure in adult hypoglycaemia.

Read the full article in Endocrinology, Diabetes & Metabolism Case Reports https://doi.org/10.1530/EDM-25-0068