Case courtesy of Joe Scofi.

 

65M history of CAD (on ASA/Plavix), HTN presents with 3 days of epigastric pain and “dark” stools.  Denies history of GI bleed. He drinks and smokes. Says that he had a AAA repair in Russia three years ago.  His vitals are: 101.3 (rectal)  105   115/65   20  98%.  He’s uncomfortable, a little jaundiced, tender in the epigastrium and guiaic (+).  The AAA repair is a red flag for aortoenteric fistula. Does this fever reassure you that this is likely some other abdominal pathology?  How would you proceed?

 

Graft infection is usually the inciting event for development of an aortoenteric fistula (AEF). So it is common for patients to present with low grade fevers. This is an example of a secondary AEF; whereas a primary AEF is from a non-grafted AAA eroding into the duodenum (and are much more rare).  So any patient with a AAA history and unexplained GI bleed is an AEF until proven otherwise. There is often a herald bleed as the vessels of the small bowel are eroded weeks before the impending aortic bleed (secondary fistulas usually form >2 years out from the graft placement).

As AEF is a disease with very high mortality, get vascular or general surgery (depending on where you are) on board early.  If the patient is stable you can CTA the aorta down to the pelvis.  It is also the study of choice for ruling out the other aortic graft complications: graft infection w/o fistula, pseudoaneurysm, and endoleak.

This patient initially was relatively stable, and got his scan, but decompensated in radiology. Obviously in the unstable patient with suspected AEF you get surgery stat, transfuse and prep for the OR.  If your surgeon isn’t convinced, they may be asking for push enteroscopy, so it would be wise to simultaneously call GI for possible emergent endoscopy. AEF is a very rare presentation, and other sources of GI bleed are much more common, so this isn’t the worst call.

But on the otherhand, they may see this: