78 下列有關梅毒的敘述，何者錯誤？
(A)第二期梅毒的病變為全身性皮疹
(B)第三期梅毒的橡膠腫（gumma），是一種肉芽腫性炎症反應
(C)第三期梅毒由於阻塞性動脈內膜炎（obliterative endarteritis）造成主動脈血管壁的破壞
(D)梅毒性主動脈炎的部位主要發生在腹部主動脈

Aneurysm of the arch of the aorta – MCC = tertiary syphilis.  Pathology of syphilis is vasculitis of arterioles. Chancre, too. Its painless b/c if you section it, you will see little arterioles surrounded by plasma cells and the lumen of the vessel is completely shut, so it is ischemic necrosis.  In other words, it is ischemia of the overlying tissue undergoing necrosis.  B/c nerves are next to vessels, they are knocked off, too, and it is painless.  All of syphilis is a vasculitis.  That is what the Treponema infects – small vessels and arterioles.  What are they affecting in the arch of the aorta? The vasa vasorum; the richest supply of vasa vasorum is in the arch, so its logical that the Treponema will pick it – leads to endarteritis obliterans (they are obliterating the lumen), ischemia, weakening under systolic pressures, leads to depression in the arch of the aorta (looks like a catcher’s mitt).  What will that do to the aortic valve ring? It will stretch it – which murmur will this lead to? Aortic regurg.  Murmurs can occur b/c there is valvular damage or b/c the valvular ring is stretched.  So, there can be stretching of the ring and nothing wrong with the valves, and have a murmur, or you can have damage to the valves and have a murmur.  Syphilis is an example of stretching of the aortic valve ring leading to a murmur and aortic regurg.