Vasculitis in the intensive care unit.

The systemic vasculitides are a diverse set of diseases linked by the presence of blood-vessel inflammation and are often associated with life-threatening or critical complications, including glomerulonephritis, diffuse alveolar haemorrhage, pulmonary arterial hypertension and airway compromise. The protean manifestations of the systemic vasculitides make them challenging to diagnose. Early recognition, however, is crucial to improving outcomes. This article serves as an introduction to these complex diseases, reviewing the manifestations of systemic vasculitis that may be encountered in an intensive care setting, and outlines an overall approach to their treatment.