Impending rupture of nonaneurysmal bacterial aortitis: CT diagnosis.

The CT appearance of mycotic abdominal aortic aneurysms leading to eventual rupture has been well described. On the other hand, ruptured nonaneurysmal bacterial aortitis has not been demonstrated in the CT literature. We present two cases with subsequent rupture documented on CT. The characteristic findings of periaortic density and adjacent gas collection should suggest the diagnosis of acute aortic infection. This may herald impending rupture, even in the absence of aneurysmal dilatation, and should direct therapy accordingly.