Evaluation of the time of patients' admission to the tertiary pediatric rheumatology center for juvenile idiopathic arthritis

Background: To determine the interval between disease onset and admission to pediatric rheumatology clinic of patients with juvenile idiopathic arthritis (JIA) and, to identify the factors that affect the admission time (AT) to rheumatology center. Methods: We designed a retrospective observational study in children with JIA. The study variables were age, gender, JIA subtype, acute phase reactants (APR), disease activity scales, presence of a pediatric rheumatologist, and distance to a pediatric rheumatology center. Outcome parameter was the duration between onset of symptoms and first visit of rheumatologist. The parameters were evaluated with variance analysis and regression models. Results: 198 patients (female:120 (60.6%)) were included. There were 112 (56.5%) patients in oligo-articular JIA, 27 (13.6%) in rheumatoid factor negative poly-articular JIA, 22 (11.1%) in enthesitis related arthritis (ERA), 29 (14.6%) in systemic-JIA, 4 (2%) in rheumatoid factor positive poly-JIA, two patients each in undifferentiated and psoriatic arthritis. The median AT in the systemic-JIA and other groups was 16 (IQR 10.5-27.5) and 71 (IQR 33.5-211) days, respectively. There was a significantly longer AT in the ERA group than others (p=0.005). We found a correlation between longer AT and older age, low back pain, enthesitis, and low erythrocyte sedimentation rate (ESR). In the multivariate analysis, only low ESR and enthesitis contributed an increase in AT [OR 2.05 (1.07-3.93), 6.22 (1.29-29.99)]. Conclusions: The older age, low back pain, enthesitis and low ESR contribute to the late AT. JIA requires high suspicion in children with poorly defined findings and low APR.