Tuesday 28 May 2013
Syphilitic aortitis (SA) is a disease of the aorta associated with the tertiary stage of syphilis infection.
Syphilitic aortitis begins as inflammation of the adventitia, including the vessels that supply the aorta itself with blood, the vasa vasorum.
As it worsens, the vasa vasorum show hyperplastic thickening of their walls that restricts blood flow and causes ischemia of the outer two-thirds of the aortic wall.
Starved for oxygen and nutrients, elastic fibers become patchy and smooth muscle cells necrose. The wall weakens and scars.
If the disease progresses, syphilitic aortitis leads to an aortic aneurysm.
Unlike atherosclerosis, which clinically manifests in older people, syphilitic aortitis typically affects those under the age of 50.
It has become rare in the developed world with the advent of penicillin treatments after WWII.
Inflammatory involvement of tertiary syphilis begins at the adventitia of the aortic arch which progressively causes obliterative endarteritis of the vaso vasorum.
This then causes narrowing of the lumen of the vaso vasorum, causing ischemic injury of the medial aortic arch and then finally loss of elastic support and dilation of the vessel.
Dissection of the aortic arch is rare due to medial scarring.
As a result of this advanced disease process, standard methods of angiography/angioplasty may be impossible for those with suspected coronary heart disease. However, these patients may be candidates for diagnostic CT as a less invasive modality.