Antineutrophil cytoplasmic autoantibodies: a review of the antigens involved, the assays, and the clinical and possible pathogenetic consequences.

INCE THE ORIGINAL description of the clinical releS vance of antineutrophil cytoplasmic antibodies (ANCA) testing for patients with vasculitis and glomerulonephritis, antibodies directed against different enzymes in granulocyte granules have been the subject of many ongoing studies.' Although the state of the art has been reviewed previously,2" new findings over the last 2 years reflect the widespread interest in this new class of autoantibodies. The Fourth International Workshop on ANCA held in Liibeck, Germany in May I992 was a clear demonstration of the recent progress in antigen identification, the development of new ANCA assays, the association of ANCA subtypes with clinico-pathologic syndromes, and the description of in vivo and in vitro models to study the pathogenic role of ANCA in vascular inflammation. In this review we summarize the present state of the art with emphasis on the most recent findings.