<prompt> Answer this question truthfullyWhat is aortitis and how can it be a characteristic feature of tertiary syphilis?  <response>: <reason> Aortitis is inflammation of the aorta, which is the largest artery in the body. In tertiary syphilis, aortitis can be a characteristic feature and is often associated with a tree-barking appearance of the aorta on imaging studies. This can be a serious complication of syphilis and requires prompt medical attention. 