Non-aneurysmal infectious aortitis: a case report.

Infectious aortitis is a rare clinical entity that is most often associated with an abdominal aortic aneurysm. There have been very few documented cases of aortitis in the setting of a normal-sized caliber aorta. We present a 67-year-old patient who presented to our Emergency Department with a history of recent fevers, fatigue, and abdominal pain. Based on an abdominal computed tomography scan, the patient was initially thought to have ruptured an abdominal aortic aneurysm of infectious etiology with extension into the left psoas muscle. Explorative laparotomy, however, revealed an infected abdominal aorta secondary to a retroperitoneal abscess with no evidence of aneurysm or pseudoaneurysm. The pathophysiology of the disease suggests that infectious aortitis and mycotic aneurysm represent extremes along a spectrum of the same disease. Establishing a diagnosis of aortic infection before the formation of an aneurysm or rupture is very difficult, but essential in preventing the devastating complications.