Clinical comparison of early-onset psoriatic and non-psoriatic oligoarticular juvenile idiopathic arthritis

Among the seven subtypes of juvenile idiopathic arthritis (JIA), oligoarticular JIA (oJIA) and psoriatic JIA (psJIA) display a predilection for onset in early childhood. We examined whether meaningful differences in clinical phenotype justify the distinction between these conditions. We performed a chart review to identify children with psoriatic and non-psoriatic oligoarticular-onset JIA. Clinical and demographic features of the two groups of children were compared. Of the 390 children included in the study, 303 met the criteria for oJIA and 87 met the criteria for oligoarticular-onset psJIA. Both groups had a peak age of onset at 2-3 years, though psJIA had appreciable incidence into adolescence. Onset before 5 years of age was observed in 215 (71%) and 38 (44%) children respectively (p