Histological insights into the pathogenesis of post-Roux-en-Y hyperinsulinaemic hypoglycaemia.

BACKGROUND β-cell hyperplasia has been implicated in the aetiology of post Roux-en-Y gastric bypass hyperinsulinaemic hypoglycaemia, but the pathogenesis of this condition is still unclear. CASE REPORT We report a case of a 52-year-old man with post-Roux-en-Y gastric bypass hyperinsulinaemic hypoglycaemia who underwent distal pancreatectomy to alleviate his symptoms. Pancreatic histopathology showed chronic pancreatitis with a corresponding loss of exocrine tissue and islet retention. Amyloid deposition was found in pancreatic islets. These features are more typically associated with Type 2 diabetes. DISCUSSION This case highlights the potential multifactorial pathogenesis of symptomatic hypoglycaemia after Roux-en-Y gastric bypass.