A 40s-year-old man was admitted to our hospital owing to severe general fatigue with blood pressure lowering. He was diagnosed with diabetic ketoacidosis as the laboratory examinations revealed hyperglycemia and metabolic acidosis. An esophago-gastro-duodenoscopy (EGD) was performed on the third day of the illness due to suspected upper gastrointestinal bleeding. Since the EGD showed circumferential blackening and white moss-like adhesions in the lower esophageal mucosa, he was diagnosed with acute necrotizing esophagitis. He was kept fasting, and was administered proton pump inhibitors and high-calorie infusions. The clinical course was good; he resumed eating on day 20 and was discharged on day 37.
