A simplified and validated ultrasound scoring system for the evaluation of synovitis in the wrists and hands of patients with rheumatoid arthritis (RA) has been proposed in a study from Beijing, China, published in Clinical Rheumatology.
A total of 705 patients >18 years old with RA who had visited the rheumatology clinic at Peking University First Hospital between February 2014 and August 2015 were recruited and assigned to group 1 in the study. All patients had ≥1 tender or swollen joint out of 22 joints examined (bilateral proximal interphalangeal, metacarpophalangeal [MCP], and wrist joints), and were evaluated with grey-scale and power Doppler ultrasound examinations. A simplified joint set assessed by an ultrasound semiquantitative scoring system was proposed based on the patients who were allocated to group 1. As a way of validating the proposed joint set, 235 patients with RA who fulfilled the same inclusion criteria and who visited the clinic from August 2015 to March 2016 were assigned to group 2.
Multiple linear regression analysis showed that the standard coefficient (β) of the MCP2, MCP3, and MCP5 joints, in terms of grey scale ultrasonography, was higher than that of the other joints. The adjusted R2 of the model consisting of wrist, MCP2, MCP3, and MCP5 joints was >0.9.
Among the sum of the grey scale plus power Doppler scores of various selected joint combinations, total score-8, which included bilateral wrist, MCP2, MCP3, and MCP5 joints, demonstrated the highest sensitivity and negative predictive value (93.86% and 92.90%, respectively, for grey scale; 97.20% and 97.21%, respectively, for power Doppler), but also the best correlation with the total score-22 (r =.955 and r =.972 for grey scale and power Doppler, respectively). The score-8 was further validated in 235 patients with RA in group 2. The sensitivity for detection of synovitis by grey scale and power Doppler was 94.35% vs 94.12%, respectively; the negative predictive values were 94.07% and 95.68%, respectively.
The investigators concluded that the 8-joint combination system, including bilateral wrists, MCP2, MCP3, and MCP5 joints, as evaluated by grey scale and power Doppler ultrasound, is valid, simple, and feasible for the detection of active synovitis in the wrists and hands of patients with RA seen in daily clinical practice.
Sun X, Deng X, Geng Y, et al. A simplified and validated ultrasound scoring system to evaluate synovitis of bilateral wrists and hands in patients with rheumatoid arthritis [published online August 22, 2017]. Clin Rheumatol. doi: 10.1007/s10067-017-3785-4