Aortoduodenal fistula.

A primary aortoduodenal fistula is usually associated with an atherosclerotic aortic aneurysm, and a secondary fistula with a leaking anastomotic aortic suture line. Two examples of each are reported. The typical features of a primary fistula are haematemesis or melaena, pain, and a pulsatile abdominal mass; the features of a secondary fistula are haematemesis and melaena with a past history of aortic resection. The initial haemorrhage is rarely fatal: a lag period allows urgent laparotomy. The fistula is diagnosed by dissection of the fourth part of the duodenum from the aorta. The treatment is closure of the duodenum, and resection of an aneurysm if present. Reconstruction is by a graft anastomosed to the aorta proximal to the fistula, if the area is clean, or by an extra anatomical bypass, if the area is heavily contaminated.