PReS-FINAL-2072: How does the management of enthesitis related arthritis differ from other sub-types of juvenile idiopathic arthritis? A retrospective study of jia at an adolescent rheumatology centre

Results The median age overall was 17.1(13-21) years. 28.9% (46) of individuals had ERA, of which 69.6% (39) were male. Mean duration of disease since diagnosis was 7.3 years (SD=+/-4.9). Of the other JIA subtypes; 21.4% (34), 17.6% (28) and 11.9% (19) had Extended Oligoarticular Arthritis (EOA), Polyarticular Rheumatoid Factor Positive (JIA RF+) and Polyarticular Rheumatoid Factor Negative (JIA RF-) JIA, respectively. There was no significant difference in mean time since diagnosis between ERA and the other JIA subgroups. The time between diagnosis and commencing a DMARD, primarily Methotrexate, was significantly longer in the ERA group (31.6 vs. 22.5 months, p = 0.008). Mean duration on Methotrexate was significantly shorter in ERA compared to EOA and JIA RF+ subgroups (31 vs. 47 and 49 months respectively, p = 0.03). 80.4% of ERA patients had been started on Methotrexate since diagnosis, with 63% continuing it at the time of the study. 57.14% of those that had stopped were discontinued due to poor treatment response. This was substantially higher than EOA and JIA RF(36.6% and 25% respectively). 17% of ERA patients had had Sulfasalazine treatment in the past compared to 5.7% and 5.8% of Polyarticular RF (polya) and EOA, respectively. The duration of Sulfasalazine treatment was significantly longer when compared with polya and EOA (36 months vs. 23 and 5 months, respectively, p = 0.034). At the time of study, a greater proportion of ERA patients were on biological treatment when compared with polya and EOA (38.9% vs. 30.7% and 17.6%, respectively, p < 0.001). 10.8% of ERA were using Infliximab compared with 0% of EOA and 1.9% of polya (p < 0.001). Adalimumab use was more prevalent amongst ERA compared with EOA and polya (13% vs. 0% and 3.8%, respectively, (p = 0.008). The time from starting a DMARD to starting a biologic was significantly shorter in ERA compared to EOA (32.8 vs. 72.4 months, p = 0.038).