Unusual clinical presentation of primary aortoduodenal fistula

Abstract

Primary aorto-enteric fistula (PAEF) develops between the native aorta and the gastro-intestinal tract, in the presence of an abdominal aortic aneurysm. It is a rare, life-threatening condition and appears to be less frequent than secondary aorto-enteric fistula, which is associated with previous aortic prosthetic reconstruction. When untreated, the overall mortality rate is almost 100%. Diagnosis may be challenging until the occurrence of a massive haemorrhage. In the presence of gross contamination, patients tend to a worse prognosis. Extra-anatomical bypass and repair of the enteric tract is the treatment of choice in case of gross contamination. In situ reconstruction is often reported in cases of mild bacterial contamination. Endovascular treatment has recently become a valid option in haemodynamically unstable patients, but a staged approach, with delayed surgical treatment, seems advisable.

Keywords: abdominal aortic aneurysm; abdominal pulsatile mass; aorto-enteric fistula; aortoduodenal fistula; gastro-intestinal bleeding.

Figure 1.

Enhanced CT scan; arrows showing: (a) absence of a clear separation between duodenal and aneurysmatic aortic wall; (b) fading contrast medium filling small bowel loop.

Figure 2.

Intra-operative findings: (a) dissected aneurysmatic wall and long thrombus extracted from the aorto-duodenal fistula; (b) extraserous aspect of the duodenal fistula facing the aneurysmatic aorta; (c) duodenal suture.