Objective: The purpose of this study was to investigate whether the presence of ultrasonographic findings of synovitis is associated with the presence of anti-cyclic citrullinated peptide (CCP) antibodies and rheumatoid factor (RF) in patients with palindromic rheumatism (PR) during active episodes.
Methods: Clinically involved regions of 84 patients with PR during active episodes were examined with high-resolution ultrasonography. Serum levels of anti-CCP antibodies were determined by an enzyme-linked immunosorbent assay, and RF levels were measured by nephelometry.
Results: Thirty patients (36%) had ultrasonographic findings of synovitis during active episodes. Significantly higher positive rates of anti-CCP antibodies and RF were observed in patients with PR who had ultrasonographic findings of synovitis compared with those who had no ultrasonographic findings of synovitis (26.7% versus 5.6%; odds ratio, 6.18; P < .05; and 30.0% versus 5.6%; odds ratio, 7.29; P < .01, respectively). The intraobserver and interobserver agreement for the detection of synovitis and Doppler signals by ultrasonographic assessment was excellent.
Conclusions: Ultrasonography is a reliable method for assessing the presence of synovitis in patients with PR during active episodes. The ultrasonographic findings of synovitis are associated with the presence of anti-CCP antibodies and RF in patients with PR.