Anti-granulocyte perinuclear antibodies but not anti-neutrophil cytoplasmic antibodies (ANCA) in rheumatoid arthritis.

We studied 45 patients with rheumatoid arthritis for the presence of ANCA. These antibodies were determined by indirect immunofluorescence (IIF) and by enzyme-linked immunosorbent assays (ELISAs) using as a substrate purified myeloperoxidase and purified extract of azurophilic granules. By IIF, we found a characteristic perinuclear immunostaining pattern in 21 cases (47%). However, no patient had a positive result by the two ELISAs performed. Patients with a positive IIF result had significantly higher levels of anti-nuclear and anti-ds DNA antibodies than those with a negative IIF result. Therefore, these antibodies must correspond to the previously reported as granulocyte specific antinuclear antibodies (GS-ANA).