Factitious brittle diabetes mellitus.

Five patients are described in whom factitious disease was the cause of brittle type I diabetes mellitus. The patients were referred from throughout the United States because their physicians had been unable to establish the reason for recurrent hospitalizations for diabetic ketoacidosis or coma. In three of the patients, unexplainable signs, symptoms, and/or laboratory results lead to the diagnosis of factitious disease. In the two remaining patients, long-term follow-up was necessary before a factitious cause was established. These five patients exemplify the extraordinary measures that some patients will utilize to continue as a "patient" rather than return to a normal lifestyle.