To Örebro University

PURPOSE: To describe clinical features, risk factors and complications in a cohort of Swedish children with juvenile idiopathic arthritis (JIA) screened for uveitis between 2002 and 2011.

METHODS: Medical records of 299 children with JIA (93 male, 206 female; median age 5.0 years at diagnosis) were retrospectively scrutinized focusing on subtype of JIA, onset of arthritis/uveitis, presence of antinuclear antibodies (ANA) and ophthalmological status.

RESULTS: Uveitis was found in 32 (11%) children, 78% bilaterally affected. The median age of arthritis onset in children who developed uveitis was 2.5 years (range 1-10) versus 5.0 years (range 1-15) in those who did not. Sex ratio was 3.5:1 (girl:boy). The most prevalent JIA subtype was oligoarthritis (75%). All but one child with uveitis was found to be ANA (+). The median interval between diagnosis of arthritis and uveitis was 12 months. Only one child developed uveitis between the fourth and fifth years after arthritis onset. Ocular complications were recorded in 45.6% (26/57 affected eyes) at last follow-up. On univariate analysis, both young age at arthritis onset and ANA positivity were possible predictors for developing uveitis, but on multivariate analysis, the latter was the most important predictor (HR 16.25, 95%; CI 2.19-120.44; p = 0.006, Cox regression analysis).

CONCLUSION: Almost all of the children developing JIA-associated uveitis did so within 4 years after arthritis onset, a fact that accentuates the importance of early initiation of ophthalmological screening and more frequent regular follow-ups during the first 4 years. The most important predictor for developing uveitis was ANA positivity.