Insulin abuse in long-standing IDDM

Two patients with insulin-dependent diabetes mellitus (IDDM) for 42 and 46 years respectively were diagnosed to produce factitious hypoglycemia. They had several properties in common: abnormal personality, refusal to stop incipient hypoglycemia, ideal body weight, good hemoglobin A1c (HbA1c) values, non-specific changes in the EEG, and brain atrophy sparing the periventricular areas. The addiction forced the patients to continue their habit during hospital stay. The dose of surreptitiously injected regular insulin always produced serum insulin concentrations large enough to clarify the diagnosis.