Abstract
A 68-year-old male with a longstanding history of severe gastric outlet obstruction secondary to peptic stricture was found unconscious at home with profound hypoglycaemia. He denied history of fasting, diabetes mellitus or use of hypoglycaemic agents. Systemic examination and metabolic profile were unremarkable. Hypoglycaemic episodes persisted during hospitalisation, requiring continuous intravenous dextrose and eventually diazoxide. Further investigative work up, including 72 h fasting study, revealed a hyperinsulinemic state. MRI and endoscopic ultrasound were unremarkable but mesenteric angiography with hepatic venous sampling revealed a subtle area of hypervascularity in the head of pancreas. An exploratory laparotomy was then performed and resulted in resection of a nodular lesion in the head of pancreas with retrocolic gastrojejunostomy for repair of pyloric stenosis. Histopathology of pancreatic nodule confirmed nesidioblastosis. Postoperatively the patient was weaned of parenteral dextrose and did not have any further episodes of hypoglycaemia.