[Anti-neutrophil-cytoplasmic antibodies in rheumatoid arthritis: specificity and clinical relevance?].

Sera of 90 patients fulfilling the criteria of the American Rheumatism Association for the rheumatoid arthritis (RA) were screened for antibodies against neutrophil cytoplasmic antigens (ANCA) by an indirect immunofluorescence test. All sera were also tested for rheumatoid factor (Waaler-Rose-Test, WRT), C-reactive protein (CRP), antinuclear autoantibodies (ANA) on HEp-2 cells. 40% of the 90 sera showed ANCA-positive reactions. c-ANCA and p-ANCA types were both observed but the latter was by far more common (91%). The peculiarity of the p-ANCA pattern was a fine granular perinuclear staining. Antibodies against myeloperoxidase (MPO) were negative in all RA sera tested. So far we found a significant relationship between positive ANCA staining, functional Steinbrocker grades, and rheumatoid factor. No significant correlation was observed with extraarticular manifestation, CRP, therapeutic modalities (gold) or MHC antigens. Currently the nature of the neutrophil antigen involved is under investigation.