Enthesitis-related arthritis: prevalence and complications of associated uveitis in children and adolescents from a population-based nation-wide study in Germany.

OBJECTIVE: Enthesitis-related arthritis (ERA) represents a subgroup of juvenile idiopathic arthritis (JIA) which is regularly accompanied by anterior uveitis. This study describes the prevalence and characteristics of ERA-related uveitis. METHODS: Cross-sectional data from the National Pediatric Rheumatological Database (NPRD) were used to characterize ERA-related uveitis (ERA-U). In addition to sociodemographic parameters, we documented the occurrence of uveitis and course of disease - including symptoms, visual acuity, and complications - as well as JIA characteristics such as disease activity (cJADAS10), functional ability (CHAQ score), laboratory parameters, and treatment. RESULTS: In the years from 2002 to 2014, 3,778 (15.2%) of a total of 24,841 JIA patients recorded in the NPRD had ERA, and 280 (7.4%) of them had developed uveitis. Detailed ophthalmological documentation by an uveitis add-on module was available for 22.9% of these patients. Uveitis onset was acutely symptomatic in 63% of patients. Patients with uveitis were more frequently male, HLA-B27 positive, and younger at ERA onset, and they had higher ESR values at first uveitis documentation than those without uveitis. Uveitis was diagnosed at a mean age of 11.5 (+/- 3.9) years (50% within two years after ERA onset). Systemic treatment with corticosteroids and synthetic and biologic disease-modifying antirheumatic drugs was associated with a (not significantly) lower risk of developing uveitis. CONCLUSION: The course of disease in ERA-U patients is frequently similar to HLAB27-associated uveitis in adults; however, a subgroup of patients presents with asymptomatic uveitis.