[Detection of antineutrophil cytoplasmic antibodies in sera from patients with rheumatoid arthritis by indirect immunofluorescence technique].

Anti-neutrophil cytoplasmic antibodies (ANCA) in sera from 52 patients with rheumatoid arthritis (RA), including 9 patients with malignant RA (MRA) and 20 healthy controls were examined by indirect immunofluorescence technique (IIF). Nine out of 52 RA patients showed positive ANCA staining. None of MRA patients had, however, ANCA in sera. The staining pattern for ANCA was either perinuclear for 4 sera or non-specific for 5 sera, but not cytoplasmic. Furthermore, anti-nuclear antibodies (ANA) in 9 ANCA positive RA sera were tested by IIF, using Hep-2 cells. Six sera had positive ANA. Three sera showed as nucleolar and 1 serum as centromere in ANA staining pattern. The incidence of these ANA staining pattern in ANCA positive sera (4 out of 9) was higher than in ANCA negative sera (1 out of 19). The clinical profiles and laboratory findings of 9 RA patients with positive ANCA revealed that they had suffered and treated for more than 10 years and had still active joint inflammation, like intractable RA. These results indicate that ANCA in RA are not associated with vasculitis.