Anti-cyclic citrullinated peptide (anti-CCP) antibody in juvenile idiopathic arthritis (JIA): correlations with disease activity and severity of joint damage (a multicenter trial)

Objectives: To determine the presence of anti-CCP antibodies in children with JIA and to correlate its levels with Juvenile Arthritis Disease Activity Score (JADAS) and Sharp/Van der Heijde Score.

Methods: The study population comprised 54 cases, with 29 patients (53.7%) who had polyarticular onset, 19 (35.2%) had pauciarticular onset and six (11.1%) had systemic onset JIA. All patients were subjected to complete clinical examination, assessment of disease activity by JADAS-27 (ESR), and radiological damage by Sharp/Van der Heijde Score. Laboratory investigations included a complete blood count, ESR first hour, ANA, IgM Rheumatoid factor (RF) and serum anti-CCP2, and were used for further correlations.

Results: RF was positive in 14 (25.9%) patients and anti-CCP antibodies were positive in 13 (24.1%) patients, 12 of whom had polyarticular onset. There were significant differences between groups relative to RF (F=8.577, P=0.001) and anti-CCP antibodies (F=4.845, P=0.012) being higher in JIA patients with polyarticular onset compared to other subsets of JIA patients. The mean total of the Sharp/Van der Heijde Score was significantly higher among polyarticular-JIA patients with positive anti-CCP antibodies compared to those negative for anti-CCP antibodies (P=0.05). Anti-CCP positively correlated with CRP (r=0.521, P<0.001) and Sharp/Van der Heijde Score (r=0.457, P<0.001).

Conclusion: Anti-CCP antibodies were prevalent among JIA patients with polyarticular patterns compared to other disease patterns. Anti-CCP positively and significantly correlated with Sharp's score and CRP levels. Given that anti-CCP may be influential in the choice of the best therapeutic strategy in JIA with polyarticular pattern of onset.