evolution of computed tomography findings in secondary aortoenteric fistula

aortoenteric fistula is a rare but significant clinical entity associated with high morbidity and mortality if remain untreated. clinical presentation and imaging findings may be subtle and prompt diagnosis can be difficult. herein, we present a patient who initially presented with abdominal pain and computed tomography showed an aortic aneurysm compressing duodenum without any air bubbles. one month later, the patient presented with gastrointestinal bleeding and computed tomography revealed air bubbles within aneurysm. with a diagnosis of aortoenteric fistula, endovascular aneurysm repair was carried out. this case uniquely presented the computed tomography findings in progression of an aneurysm to an aortoenteric fistula.