[Hypoglycemia caused by insulinoma in diabetes mellitus]

An hyperglycaemic metabolic state disappeared and spontaneous hypoglycaemia occurred in a 58-year-old woman with non-insulin-dependent obese type II diabetes. Abnormal absence of the hunger response with provoked hypoglycaemia, increased serum insulin concentrations and reduced blood glucose/insulin ratio led to the diagnosis of pathological hyperinsulinism, which was found to be due to an insulinoma of the tail of the pancreas. After its excision the patient's carbohydrate metabolism returned to a mild type II diabetic state and there were no further hypoglycaemic attacks.