**1. Introduction**

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216 Updates in the Diagnosis and Treatment of Vasculitis

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Small vessels refer to arterioles, capillaries and venules. According to an international consensus conference, small vessel vasculitides include, ANCA-associated vasculitis (granulomatosis with polyangitis [Wegener's], Churg-Strauss syndrome, microscopic pol‐ yangiitis), cryoglobulinaemic vasculitis, Henoch-Scholein purpura, and cutaneous leuko‐ cytoclastic angiitis [1].
