Subclinical synovitis frequently precedes the development of inflammatory arthritis among anti-cyclic citrullinated peptide (CCP) 2- positive at-risk individuals with musculoskeletal symptoms but no clinical synovitis (CCP2+ at-risk), according to a study published in Rheumatology. Andrea Di Matteo, MD, PhD, and colleagues reviewed ultrasound (US) scans of CCP2+ at-risk individuals who developed inflammatory arthritis for subclinical synovitis prior to development of inflammatory arthritis. Predictors of US synovitis in CCP2+ at-risk individuals without baseline US abnormalities were also identified. The investigators detected US subclinical synovitis on one or more scans in 77.3% of 97 progressors (median time from first evidence of US synovitis to inflammatory arthritis, 26.5 weeks). Among 220 CCP2+ at-risk individuals with normal baseline US scans, US synovitis was detected in 69 patients (31.4%; median time to first developing US synovitis, 56.4 weeks). Only anti-CCP3 antibodies were predictive for development of US synovitis in a multivariable analysis (OR, 4.75).