Factitious hypoglycemia: an unusual clinical picture within Von Münchausen's syndrome

Two cases of hyperinsulinism from insulin self-administration are described, both patients being admitted to hospital with a diagnosis of insulinoma. In the first case, the diagnosis was clarified after a left pancreatectomy elsewhere, thanks to the discovery of a bottle of insulin. In the second case, the diagnosis was confirmed by the measurement of C-peptide during a hypoglycemic attack. The simultaneous sharp decrease in glucose levels, an exceptional increase in insulinaemia and a reduction or disappearance of serum C-peptide is indicative of this particular type of hyperinsulinism. The two cases described here were remarkably similar. Apart from the most common features, both reported a severe hypoglycemic syndrome of recent onset; negative tolbutamide and calcium tests; a frequent relapse shortly after glucose administration.