Arterioenteric fistulas.

Any patient with an abdominal aortic aneurysm, aortic graft or previously resected infected graft who presents with gastrointestinal bleeding or sepsis must be assumed to have an arterioenteric fistula. Warning bleeds are common. Oesophagogastroduodenoscopy may be diagnostic and should exclude other causes of upper gastrointestinal haemorrhage. Urgent investigation and surgery are essential for a successful outcome.