Magnetic Resonance Imaging Followup of Temporomandibular Joint Inflammation, Deformation, and Mandibular Growth in Juvenile Idiopathic Arthritis Patients Receiving 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 patients with JIA (29 female, median age 9.0 yrs, interquartile range 6.2-10.7 yrs) receiving systemic therapy with TMJ involvement, with 2 TMJ magnetic resonance imaging (MRI) examinations ≥ 2 years apart and no TMJ corticosteroid injection. Clinical and MRI findings were compared between initial and followup examinations and between TMJ with and without active inflammation at baseline. RESULTS: Over a median period of 3.6 years (range, 2.0-8.7 yrs), MRI grade of TMJ inflammation improved (p = 0.009) and overall osseous deformity tended to become less severe (p = 0.114). In TMJ with arthritis at baseline (46 TMJ), both the grades of inflammation (p < 0.001) and deformity (p = 0.011) improved. In TMJ with no arthritis at baseline (30 TMJ), the frequency and grade of condylar deformation remained stable. Mandibular ramus growth rates were not significantly different between TMJ with and without arthritis at baseline (1.3 mm/yr vs 1.5 mm/yr, 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 followup than at initial examination (24% vs 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 of 36 disks were displaced. In total, 28 of 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). In total, 19 of 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 of 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 of 31 joints with ADD and decreased in 26 of 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.

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

OBJECTIVE: 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. METHODS: 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. RESULTS: 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. CONCLUSION: 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 indication.