Objectives To investigate the diagnostic value and prognostic usefulness of anti-citrullinated protein/peptide antibodies (ACPA) in children with juvenile idiopathic arthritis (JIA).

Methods The presence of ACPAs in the serum samples from 81 JIA patients were determined using Anti-CCP IgG, CCCP3.1 IgG and IgA ELISA. Citrullinated Protein Antibodies, Anti-MCV, and Aeskulisa RA/CP-Detect which coated various citrullinated antigen substrates: synthetic cyclic peptide, recombinant rat filaggrin, mutated human vimentin, and IgG-derived peptides. 55 children with other joint diseases and 49 healthy donors were control groups. The diagnostic performance of ACPAs was analyzed and correlations between ACPAs and radiological damage were evaluated.

Results CPAs in 8.8–28.4% of JIA group were detected with specificity of 84.6–98.1%. ACPAs could be seen in all subtypes of JIA, and high levels of ACPAs were particularly found in the RF positive JIA patients No healthy control had increased ACPA tested for CCP, CCP3.1, and CPA, whilst 3and 2 of healthy controls were found positive to MCV and RA/CP, respectively. The presence of ACPAs correlated more frequently with the presence of RF (P<0.05). The ACPA positivities in 18 JIA patients with radiological damage were 27.8–55.6%, which higher than that in patients without damage, and of the ACPA (CCP, CCP3.1, CPA, or MCV) positive JIA patients, 62.5%, 62.5%, 52.9%, 43.5% respectively had radiological damage, which significantly higher than that in JIA patients without ACPA (P<0.05).

Conclusions This study confirms the main presence of ACPAs in children with polyarticular JIA, especially those with RF positive using ELISA based methods, and ACPAs relate significantly with joint erosions in JIA.

Disclosure of Interest None declared