SAT0055 Two-Year Outcome in 495 Patients with Undifferentiated Arthritis of Very Short Duration

BackgroundUndifferentiated arthritis (UA) is defined as cases of inflammatory arthritis where no definitive diagnosis can be made, and that may evolve into a chronic inflammatory disease over time or result in persistent drug-free remission.ObjectivesIn this study we investigated the 2-year disease course in patients with poly-, oligo- and monoarticular UA, with the main outcomes being 1) fulfillment of the 2010 ACR/EULAR RA classification criteria, 2) absence of clinical synovitis without use of DMARDs and 3) final clinical diagnosis.MethodsPatients (18-75 years old) with ≥1 swollen joint of