title: A rare cause of syncope in a patient with diabetes mellitus--a case report.
abstract: BACKGROUND
  Hypoglycaemic episodes in patients with diabetes mellitus are mostly due to excess doses of exogenous insulin or oral hypoglycaemic agents, coupled with poor caloric intake and excessive unplanned physical exertion. Hypoglycaemia as a result of endogenous hyperinsulinaemia due to an insulinoma is extremely rare in such patients.
  
  
  METHODS
  This patient with type 2 diabetes mellitus presented with episodes of syncope. Investigations confirmed recurrent hypoglycaemia from endogenous hyperinsulinaemia, with localisation of a tumour in the tail of the pancreas.
  
  
  METHODS
  Distal pancreatectomy and splenectomy. Histology confirmed an insulinoma.
  
  
  RESULTS
  No further hypoglycaemic episodes were noted. The patient returned to his diabetic state with rather poor glycaemic control.
  
  
  CONCLUSIONS
  Repeated hypoglycaemic episodes in a patient with diabetes mellitus despite complete withdrawal of hypoglycaemic agents should lead one to consider other causes of hypoglycaemia.
authors.affiliation: Department of Medicine, Changi General Hospital.
authors.forename: S
authors.initials: S
authors.lastname: Tavintharan
authors.forename: J J
authors.initials: JJ
authors.lastname: Mukherjee
mesh_terms: D003924:Diabetes Mellitus, Type 2 / Q000150:complications*; D006801:Humans; D007003:Hypoglycemia / Q000209:etiology*; D007340:Insulinoma / Q000150:complications* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D010190:Pancreatic Neoplasms / Q000150:complications* / Q000601:surgery; D013575:Syncope / Q000209:etiology*