To investigate the ultrasound features of gouty joints during acute and past attacks.

Clinical data and ultrasound features of joints during the acute and past attacks of gouty patients who were experiencing an acute attack were collected. The differences of ultrasound features between two episodes, as well as the relationship with clinical characteristics were analyzed.

Sixty-four patients were enrolled with 21(33%) patients at their first attack. The first metatarsophalangeal (MTP1) joints were most frequently involved, meanwhile, 9.4% patients had two or more joints attacked during one episode. The most prevalent feature was synovitis at the acute phase, followed by double contour (DC) sign (18 cases, 28%), bone erosion (12 cases, 19%) and tophi (10 cases, 16%), while 23 patients had two or more pathological changes. Whereas, the DC sign was found most in previously attacked joints (10 cases, 33%), followed by tophi (8 cases, 27%), bone erosion (7 cases, 23%) and synovitis (4 cases, 13.3%). No positive pathological changes were found in asymptomatic joints. Synovitis was more common in joints during their acute attacks (80% vs 13%, χ²=20.475, P<0.01), however, DC sign and tophi were more common in previous attacked joints (10% vs 33% and 0 vs 27%, χ²=3.892, 6.642, P<0.05, respectively). Both the DC sign and tophi were positively correlated with the disease duration.

Synovitis is the most prevalent feature in gouty joints during acute episodes; even bone erosion can be found at the first attack. The DC sign, tophi and bone erosion are common in past attacked joints. The prevalence of both DC sign and tophi are increased along with disease durations. Subclinical synovitis can be detected in a small past of joints which are not at acute attack.

Gouty arthritis; Musculoskeletal Ultrasound; Acute attack; Previously attacked joints.