Magnetic Resonance Imaging Follow-up of Temporomandibular Joint Inflammation, Deformation and Mandibular Growth in Juvenile Idiopathic Arthritis Patients on Systemic Treatment

OBJECTIVE To investigate the course of temporomandibular joint (TMJ) inflammation, osseous deformation and mandibular ramus growth in children with juvenile idiopathic arthritis (JIA) during systemic therapy. METHODS Longitudinal study of 38 consecutive JIA patients (29 female, median age 9.0 years, interquartile range 6.2 to 10.7 years) on systemic therapy with TMJ involvement, with two TMJ magnetic resonance imaging (MRI) examinations ≥ 2 years apart and no TMJ corticosteroid injection. Clinical and MRI findings were compared between initial and follow-up examinations and between TMJs with and without active inflammation at baseline. RESULTS Over a median period of 3.6 years (range, 2.0-8.7 years), MRI grade of TMJ inflammation improved (p=0.009) and overall osseous deformity tended to become less severe (p=0.114). In TMJs with arthritis at baseline (46 TMJs), both the grades of inflammation (p<0.001) and deformity (p=0.011) improved. In TMJs with no arthritis at baseline (30 TMJs), the frequency and grade of condylar deformation remained stable. Mandibular ramus growth rates were not significantly different between TMJs with and without arthritis at baseline (1.3 mm/year versus 1.5 mm/year, p=0.273), and were not correlated with the degree of inflammation at baseline or followup. The frequency of facial asymmetry tended to be lower at follow-up than at initial examination (24% versus 45%, p=0.056). CONCLUSION Our results suggest that systemic treatment of TMJ arthritis in children with JIA decreases the degree of inflammation seen on MRI, preserves osseous TMJ morphology and maintains normal mandibular ramus growth

Temporomandibular joint magnetic resonance imaging findings in adolescents with anterior disk displacement compared to those with juvenile idiopathic arthritis

BACKGROUND Deformation of the mandibular condyle can be associated with anterior disk displacement (ADD) or involvement of the temporomandibular joint (TMJ) by juvenile idiopathic arthritis (JIA). Diagnostic differentiation is critical for proper management. OBJECTIVES To compare morphology and inflammation between TMJs with ADD and JIA. METHODS Retrospective assessment of contrast-enhanced TMJ MRI in 18 adolescents (15 female, mean age 15.1±1.9 years) with ADD and age- and gender-matched patients with JIA. Articular disk findings, inflammatory signs and osseous morphology were compared. RESULTS In the ADD-group, 31/36 disks were displaced. 28/31 displaced disks showed thickening of the bilaminar zone. In JIA patients, the disks were mainly flattened (19/36), centrally perforated (12/36) and/or anteriorly displaced (2/36). 19/31 TMJs with ADD showed various degrees of inflammation, with joint effusion, synovial thickening and joint enhancement not significantly different from JIA patients. Osseous deformity was present in 27/31 TMJs with ADD, with frequent erosions in both groups (ADD 25/31; JIA 32/36, p=0.55) but lower grades of condylar and temporal bone flattening than in JIA (p≤0.001). Glenoid fossa depth was preserved in 28/31 joints with ADD and decreased in 26/36 joints with JIA (p<0.0001). Mandibular ramus height was decreased in both groups. CONCLUSION In adolescents, inflammatory signs are common MRI findings in symptomatic TMJs with ADD and thus should not be considered diagnostic for JIA involvement. In this cohort, both entities had high rates of condylar deformity, while TMJs with ADD showed a better-preserved and often normal shape of the glenoid fossa. This article is protected by copyright. All rights reserved

Prevalence of Anti-infliximab Antibodies and Their Associated Co-factors in Children with Refractory Arthritis and/or Uveitis: A Retrospective Longitudinal Cohort Study

Infliximab (IFX) is a monoclonal tumor necrosis factor-α-inhibiting antibody used in children with refractory arthritis and uveitis. Immunogenicity is associated with a lack of clinical response and infusion reactions in adults; data on immunogenicity in children treated with IFX for rheumatic diseases are scarce. We aimed to describe the prevalence of anti-IFX antibodies and determine co-factors associated with anti-IFX antibodies in children with inflammatory rheumatic and ocular diseases. Consecutive children treated between August 2009 and August 2012 with IFX at our department were included. Blood samples were collected every 6 months before IFX infusion and tested for anti-IFX antibodies by radioimmunoassay. Patients' charts were retrospectively reviewed for clinical features and analyzed for associations with anti-IFX antibodies. Anti-IFX antibodies occurred in 14/62 children (23%) and 32/253 blood samples (12.6%) after a mean treatment time of 1084 days (range 73-3498). Infusion reactions occurred in 10/62 (16%) children during the treatment period. With continuation of IFX, anti-IFX antibodies disappeared in 7/14 children. In the bivariate analysis, the occurrence of anti-IFX antibodies was associated with younger age at IFX treatment start (mean age 7.01 vs 9.88 yrs, p = 0.003) and infusion reactions (OR 15.0), while uveitis as treatment indication was protective against development of anti-IFX antibodies (OR 0.17), likely because of higher IFX doses. In the multivariate logistic regression, all 3 covariates remained highly significant. Anti-IFX antibodies occurred commonly at any time during IFX treatment. Anti-IFX antibodies were associated with younger age at IFX start, infusion reactions, and arthritis as treatment indicatio