Pharmaceutical error resulting in fatal diabetic ketoacidosis

A 41-year-old male with a 25-year history of diabetes mellitus requiring 25 to 30 units of neutral protamine hagedorn (NPH) insulin daily was found dead at home. Recent history revealed that he was well until the last four days of life when he had the onset of nausea, vomiting, and anorexia coinciding with procurement of a new bottle of insulin from his pharmacist. Pertinent autopsy findings included coronary and aortic atherosclerosis, a peptic ulcer, and diabetic glomerulopathy. Chemical analysis of the vitreous humor, including glucose (813 mg/dL) and acetone (40 mg/dL), revealed that he died of diabetic ketoacidosis. Further investigation revealed that the pharmacist had accidentally substituted regular insulin, with a duration of action of up to 6 h as opposed to 24 to 28 h, for NPH. Cultures of blood and of the regular insulin yielded no growth. Analysis of this case emphasizes the importance of obtaining a careful medical and medication history and the usefulness of vitreous electrolytes when investigating a sudden death in a diabetic.