The systemic vasculitides.

The systemic vasculitides include a heterogenous group of diseases, characterized by inflammatory and necrotic lesions of the vessel walls, with subsequent ischemic changes in different organs. Various factors are incriminated in the vasculitides etiology, despite the fact that, in most of the cases, the etiologic agents are unknown. The pathogenic mechanisms are generally mediated through circulant immune complexes, which induce the inflammatory reaction at the vessel wall site, accompanied by complex immune reactions. A classification of vasculitides should take into account the type of the injured vessel, the elements of the inflammatory infiltrate and the triggering pathogenic mechanisms. The definition and monitoring of the therapeutic regimen are difficult but, generally, the main elements of medication are represented by corticosteroid and cytotoxic drugs.