Aortoenteric Fistula - Diagnosis and Management Summary Epidemiology: • Uncommon but life-threatening • Most common site of bowel connection is the duodenum Clinical Signs/Symptoms: • Classic triad: Bleeding, abdominal pain, and palpable abdominal mass - Not reliable, so diagnosis requires high index of suspicion • Should be on differential for any patient with known AAA or prior aortic intervention, no matter how long ago • Gl bleeding is most common presentation • Minor hemorrhage may be herald bleed • Massive, life-threatening bleeding or rapid exsanguination • Typical "herald bleed": episode of seemingly self-limited gastrointestinal bleeding that precedes a later catastrophic episode of hemorrhage. Pathophysiology: • Primary AEF: arises de novo between aorta and bowel, usually as result of compression of AAA against bowel. • Secondary AEF: More common. Develops following any surgical aortic reconstruction; erosion of prosthetic graft into surrounding bowel Diagnosis: • HD unstable patients with massive bleed and known AAA (unrepaired or repaired) should be taken directly to the OR • HD stable patients with acute Gl bleeding may undergo EGD - Sensitivity of EGD for dx AEF is only about 50% • Stable patients with a high suspicion for AEF: CTA is first-line study - If negative, EGD should be performed with careful inspection of the distal duodenum. • CT findings that correlate strongly with the presence of AEF: Ectopic gas adjacent to or within the aorta, focal bowel wall thickening, discontinuity of the aortic wall, extravasation of contrast material into the bowel lumen. Management: SURGERY! - CMC IM Residency @CMC_IM #Aortoenteric #Fistula #Diagnosis #Management #Summary #vascular
