ABSTRACT
Antibodies against cyclic citrullinated peptide [Anti-CCP] are considered to be specific for rheumatoid arthritis [RA]. To assess the clinical significance of anti-CCP antibodies in JIA, i.e. to determine if it can be detected in JIA patients and if they can be used to identify patients with a more destructive course of the disease. Fifty five JIA patients were included in this study. They represented the majority of subtypes of JIA patients. They were 14 boys and 41 girls with mean age 12.5 +/- 2.1 [Range 8-15.5 years] and mean disease duration 4.5 years [range 1-7.5 years]. One or more sera was taken from the patients at different time points of the disease course, 75 sera samples were analyzed using a commercial Kit using an Enzyme Linked Immunosorbent [ELISA] Assay. Our results showed that anti-CCP was positive in 7 patients [12.7%], 5 with polyarticular IgM-RF positive i.e. 5/12 [41.6%] and another 2 with oligoarthritis. This means that there was a significant difference between the prevalence of anti-CCP positivity in polyarticular IgM-RF positive subtypes and the other subtypes [p<0.05]. Disease duration, medications, and antinuclear antibody positivity effect did not show any significant difference between anti-CCP positive and negative patients. Follow up samples at different times also showed no significant difference of the anti-CCP results. Radiological joints damage was seen in 23 patients out of all the patients evaluated [41.8%]. All the patients with positive IgM-RF had radiological changes denoting joint damage, while 5/7 of anti-CCP positive JIA patients [71.4%] had those radiological changes with significant difference between anti-CCP positive and anti-CCP negative patients. Our study showed that anti-CCP autoantibodies can be detected in the sera of juvenile idiopathic arthritis patients, most exclusively in polyarticular IgM-RF positive patients. Longer prospective study with more patients sample will be necessary to verify whether these JIA patients with positive IgM-RF and anti-CCP constitute a differential subgroup with progressive destructive course similar to those of adult RA patients