[Vasculitides--introduction]

Vasculitis is clinicopathologic process characterized by inflammation and damage of blood vessels, often resulting in complete or partial occlusion of the involved vessels and ischemic damage to the supplied organ or tissue. The vasculitides are a large group of heterogeneous diseases for which it has been assumed that pathogenesis is largely autoimmune. It may be a primary or secondary manifestation of a disease process and may affect single or multiple organs. Inflammation affects vessel's walls partly or completely resulting with the loss of vascular integrity. Vasculitides has been classified by whether inflammation predominantly damage small, medium, or large vessels.