Occurrence of autoantibodies against neutrophil granulocyte components in juvenile chronic arthritis

This study included 96 patients with juvenile chronic arthritis of whom 47% had antinuclear antibodies (ANA). The highest frequency (58%) was seen in the oligoarticular subset, followed by the polyarticular and systemic subsets with ANA in 42% and 17% of the patients, respectively. Sixteen patients (17%) of whom 13 belonged to the polyarticular subset had granulocyte specific ANA (GS-ANA) with a titre greater than or equal to 1/50. Still another 22 patients (23%) had a borderline titre 1/25. GS-ANA were not found in any patient belonging to the systemic subset. Two of 16 patients with chronic iridocyclitis were GS-ANA positive while 9 were positive for ANA. None of the patients had circulating antibodies to neutrophil cytoplasmatic antigens (ANCA) detected by immunofluorescence or antibodies to elastase measured by ELISA. Antibodies to myeloperoxidase were found by ELISA in one patient, who showed no deviating clinical characteristics.