Hypoglycaemia in a patient who is non-diabetic

A 59-year-old Caucasian man was seen in clinic following general practitioner's referral presenting with a 1-year history of hypoglycaemia. It was deemed important given his history that an insulinoma should be ruled out. The patient had an induced episode of hypoglycaemia while under medical supervision; C-peptide, insulin and insulin-like growth factor levels were measured. These results strongly suggested an insulinoma. He was subsequently referred to our local tertiary centre for surgical workup and excision of the insulinoma. This case reminds us that insulinoma, although rare, is an important differential to rule out in non-diabetic hypoglycaemia. Often the diagnosis is overlooked as their symptoms mimic many other conditions. Although there is no specific Driver and Vehicle Licensing Agency advice, we, as the healthcare provider, should be ensuring the patients inform them.