The human vasculitis syndromes.

The vasculitides consist of a spectrum of clinical syndromes having in common necrotizing inflammation of the vascular system. Typical classification systems are based on both size of vessel involved and clinical gestalt. The author favors a pragmatic classification. Symptoms are manifestations of systemic inflammation and of organ ischemia secondary to inflammatory vascular occlusion. Multicenter studies suggest that the most common vasculitides do not satisfy criteria for one of the specific nosological entities and would be classified as "other" vasculitides. For those syndromes fitting a classical description (e.g., Wegener's, polyarteritis nodosa, Henoch-Schoenlein purpura), therapy is straight-forward. For those defying classification, therapy must be empirically directed at the manifestations causing symptoms.