What does the word polyangiitis mean? (related to the name change).

“Poly” indicates that many blood vessels are involved, and “angiitis” is used instead of “arteritis” because granulomatosis with polyangiitis (Wegener’s) and microscopic polyangiitis affect the smallest vessels in the body (arterioles, capillaries, and venules), all of which are smaller than arteries. In contrast, in polyarteritis nodosa, giant cell arteritis, and Takayasu’s arteritis, only arteries (either a little or much larger than arterioles) are affected.

(Click the back button in your browser to go back to the FAQ page.)