Anti-cyclic citrullinated peptide antibodies in juvenile idiopathic arthritis.

Objective. Prevalence and clinical significance of anti-cyclic citrullinated peptide (CCP) antibodies in Indian patients with juvenile idiopathic arthritis (JIA). Methods. Anti-CCP antibodies were determined by enzyme-linked immunosorbent assay (ELISA) in 78 patients with JIA which included all 3 major subtypes of the disease: pauciarticular, polyarticular afld systemic onset. Values above 5 relative units were taken as positive. Associations between antiCCP antibodies and clinical and laboratory and radiological parameters were determined. Results. Anti-CCP antibodies were positive in only 2 of 34 (5.9%) patients with pauciarticular JIA and 3 of 17 (17.6%) of systemic,.pnset JIA, whereas it was positive in 13 of 27 (48.1%) of polyarticular JIA patients (p < 0.001). Furthermore, it was seen that among patients with polyarticular JIA, RF-lgM positive patients had higher rate of anti-CCP antibody positivity with 7 of 8 (87.5%) patients having positive anti-CCP antibody (p<0.001). Similarly, patients with erosions (11/19; p<0.001) and deformities (5/-10; p<0.001) were found to have significant association with anti-CCP antibody positivity. Conclusion. Anti-CCP antibodies could be detected more frequently in the sera of JIA patients with severe manifestations like- erosions and deformity. It was also more significantly associated with seropositive polyarticular JIA than other types. It can be presumed from these results that anti-CCP antibodies can be used as a marker to predict severe course of JIA at the onset to guide optimal aggressive therapy.