Laboratory investigation in the diagnosis of vasculitis.

Few tests have been firmly established to diagnose primary systemic vasculitides. Although antineutrophil cytoplasmic autoantibodies (ANCA) are an exception, no consensus exists on the best method to detect them and they have proved of limited aid in relapse prediction. This article discusses common methods and techniques used to detect ANCA, their clinical usefulness, and recent biomarkers that may replace ANCA in established disease.