Medical Follow-up of New Cases of Polyarthritis in Children and Young Adults

This study is proposed by the Rheumatology and Pediatrics departments of the 3 French-speaking Universities. The first objective will be to include a progressive number of new young patients (≤ 50 years) in order to optimize and standardize care and clinical response objectives. The number of 25% of new incident cases will be sought with an increase of 20% each year during the 5 to 10 years of this project. Population: JIA, RA/UA, SLE, dSS (American Congres of Rheumatology criteria). Naïve to basic treatment OR treated for ≤ 3 months; except for patients with JIA. These 5 cohorts will be subject to standardized clinical monitoring and specific objectives that will make it possible to analyze the number of patients with a good control of the disease and/or a clinical remission, defined according to the international criteria.