Ultrasound detection of aortoenteric fistula in a patient with sepsis

We report a case of an 81-year-old man, hospitalized for sepsis unresponsive to targeted antibiotic therapy, who underwent abdominal aortic aneurysmectomy with stent placement before 12 years. Point-of-care ultrasound examination showed the presence of a voluminous and inhomogeneous lesion adjacent to the anterior wall of aortic bifurcation with pulsatile flow from the aorta into the lesion, highlighted by Color-Doppler, and peripheral (closely with intestinal loops) floating hyperechoic spots marked by posterior comet tail artifact, suggestive for the presence of air bubbles. The presence of an aortoenteric fistula not excluding in differential diagnosis and the possibility of an abscess of aneurysmatic sac with colonization of gas-producing bacteria were suspected; an abdominal contrast-enhanced computed tomography was requested and it confirmed the suspicion of an aortoenteric fistula. The patient underwent emergency surgical intervention with good technical success (evidence of aorto-appendicular fistula), but he died the day after of cardiac arrest.