A 71-year-old man with hyperglycemia and mental status changes.

Hyperglycemic hyperosmolar syndrome is an extreme but relatively common presentation of uncontrolled or new-onset diabetes mellitus. The diagnosis of the disorder itself is fairly straightforward, but the search for an underlying cause can be challenging. Infections are the usual precipitating factor, but a variety of other stressors can be involved. We report herein a patient presenting with hyperglycemic hyperosmolar coma with three possible precipitating infections: pharyngitis, urinary tract infection, and infective endocarditis.