Anti-cyclic Citrullinated Peptide Antibodies in Patients with Juvenile Idiopathic Arthritis

Abstract

We analysed the presence of anti-cyclic citrullinated peptide (anti-CCP) and anti-keratin (AKA) antibodies of the IgG class in sera of patients with defined juvenile idiopathic arthritis (JIA) of various subgroups with more than one year duration of the disease. Enzyme-linked immunosorbent assay (Immunoscan RA, Eurodiagnostica, The Netherlands) and an indirect immunofluorescence (IIF) test on rat oesophagus substrate (ImmuGloTM, Immco Diagnostics, Buffalo, USA) were used for the detection and quantification of anti-CCP and AKA antibodies in 140 patients with JIA (64 male and 76 female) aged 2-47 years (median 16.5 years). Overall, anti-CCP were found in 7/140 (5.0%) patients including 3/52 RF negative polyarthritis, 2/18 RF positive polyarthritis, 1/15 enthesitis related arthritis and 1/5 unclassifiable arthritis. AKA were detected in 40/140 patients (28.6%, p = 0.04) including 2/11 systemic arthritis, 2/32 oligoarthritis, 18/52 patients with RF negative polyarthritis (34.6%, p = 0.01), 14/18 RF positive polyarthritis (77.8%, p = 0.000002), 2/15 enthesitis related arthritis and 2/3 psoriatic arthritis. While simultaneous negativity for AKA and anti-CCP occurred in most (97/140; 69.3%) studied cases, simultaneous antibody positivity was found only in few (4/140; 2.9%) studied samples. We conclude that while AKA measured using IIF on rat esophagus can be detected approximately in one third of patients with definite JIA with more than 1 year duration of the disease, only rare occurrence of anti-CCP was observed. We conclude that AKA seem to be partly useful to confirm JIA diagnosis, however, useless to follow-up severity or activity in JIA patients. Anti-CCP do not have any additional value in MA cohort in comparison to RA where their diagnostic and prognostic importance was reported.

Anticyclic citrullinated peptide antibodies in juvenile idiopathic arthritis

“…18 The first three studies about anti-CCP Abs in childhood reported 2%-5% anti-CCP positivity. [12][13][14] Hromadnikova et al found seven children (5%) with anti-CCP. Two of them were diagnosed as having RF polyarticular JIA.…”

“…[12][13][14][15][16][17][18][19] Five of them investigated children with JIA, but in the other studies, patients with JIA served as the control group for RA. In the study of Lee all anti-CCP-positive patients had an RF-positive polyarticular JIA, 19 and Bizarro et al found none of their three JIA patients to be anti-CCP positive.…”

“…Overall, anti-CCP Abs were found in 5% (7/140) patients including 3/52 RF-negative polyarthritis, 2/18 RF-positive polyarthritis, 1/15 ERA, and 1/5 unclassifiable arthritis. 13 Kasapçopur et al detected anti-CCP Abs in 2% (3/122) of children with JIA. Twelve of them had RF-positive polyarticular JIA.…”

Anticyclic Citrullinated Peptide Antibody: A Predictor of Juvenile Idiopathic Arthritis Progression Toward Rheumatoid Arthritis

“…The patient with polyarticular onset was RF-negative. In another study, Hromadnikova et al [5] scrutinized the presence of anti-CCP Abs in sera of 140 patients with JIA aged 2-47 years. Overall, anti-CCP Abs were found in 5% (7/140) patients including 3/52 RF-negative polyarthritis, 2/18 RF-positive polyarthritis, 1/15 ERA, and 1/5 unclassifiable arthritis.…”

“…However, their presence fis not reflated to tThe dfisease course or to tThe severfity off tThe jofint involvement [2]. Anti-CCP Abs have been studied in children a few times [3][4][5][6][7]. Reviewing the literature, Low et al [7] found anti-CCP Abs in 77% (51/66) patients with JIA, including 15/18 (83%) RF-negative polyarthritis, 12/16 (75%) RF-positive polyarthritis, 16/19 (84%) oligoarthritis, 8/13 (62%) systemic arthritis.…”