Presentation of Case A 25-year-old man was admitted to the hospital because of the recent onset of congestive heart failure and atrial fibrillation. The patient had been well until four months earlier, when he had a severe upper respiratory tract infection, which resolved with one week of bed rest at home. Two months before admission he was admitted to another hospital because of polydipsia, polyuria, polyphagia, and a weight loss of 9 kg. The blood glucose concentration was as high as 437 mg per deciliter (24.3 mmol per liter). Radiographic study of the chest and an ultrasonographic examination of the.