Diagnosing aortic syphilis.

Described herein is a morbidly obese 57-year-old man with an aneurysm involving the tubular portion of the aorta. Examination of the wall of the operatively resected aneurysm disclosed classic findings of aortic syphilis, a condition that clearly has not disappeared. If there is an aneurysm involving the tubular portion of the ascending aorta in the absence of aortic dissection or involvement of the sinuses of Valsalva, the most likely diagnosis is aortic syphilis. In these circumstances, the serologic test for syphilis is often negative.