OBJECTIVES: The prevalence of juvenile idiopathic arthritis (JIA) is approximately 3.3/1000 children and 10-15% have the systemic form (SJIA). Biologics, specifically anti-IL1 and anti-IL6 therapy have dramatically reduced the prolonged use of corticosteroids and therefore decreased the associated morbidity including growth failure, cataracts, fractures and body image problems.  This study aims to determine the prevalence of SJIA and biologic use in SJIA in Ontario. METHODS: All patients seen at the Rheumatology Clinic of the Hospital for Sick Children (SickKids), Toronto with a diagnosis of SJIA from December 1986 to January 2013 were eligible.  Exclusion criteria: Diagnosis not confirmed, <1 year follow-up, <1 visit per year and unable to obtain complete medical record.  Data for Ontario SJIA prevalence was estimated through personal communication with all practicing pediatric rheumatologists in Ontario. RESULTS: The cohort consisted of 268 SJIA patients which represented 13% of the total JIA cohort.  Since 2012, when anti-IL-1 and anti-IL-6 medications were readily available in Ontario, 12/23 (52%) of newly diagnosed patients received either anti-IL-1 or anti-IL-6 (11/12 received anti-IL-1 therapy).  In the other 3 pediatric rheumatology centres in Ontario, 9 additional SJIA patients were diagnosed and 3 received anti-IL-1 and 2 anti-IL-6. Medication choice was based on the patient’s drug coverage, patient/parent preference for intravenous vs. subcutaneous mode of administration and distance from an infusion centre. No other biologic (anti-TNF for example) was started in any of these patients. CONCLUSIONS: In Ontario there are approximately 150 patients with SJIA followed by pediatric rheumatologists. Although this group constitutes a small proportion of the total JIA population, they require more intensive therapy with 50% treated with a biologic as compared to 10-15% of total all JIA patients currently followed at SickKids.