Objective  To analyze the value of power Doppler ultrasound score of hand joints (PD scores) in predicting the therapeutic effects of tropizumab (TCZ) in the treatment of moderate to severe rheumatoid arthritis (RA).

  Methods  Totally 80 patients with moderate to severe RA from April 2017 to April 2018 were selected and treated with TCZ at a dose of 8 mg/kg once per week for 24 weeks. At the same time, they were treated with DMARDs and hormones as appropriate. The levels of erythrocyte sedimentation rate (ESR), C reactive protein (CRP), white blood cell count (WBC), rheumatoid factor (RF), platelet count (PLT), 28 joint disease activity integral (DAS28)-ESR, DAS28-CRP and the synovial membrane thickness, the PD score of the hand joints at the time points of hospital admission, 12 weeks and 24 weeks of TCZ treatment were observed and analyzed in all the patients. The proportions of the patients met the standard of American College of Rheumatology (ACR) 20 at 12 weeks and 24 weeks of TCZ treatment were evaluated and analyzed.

  Results  With the implementation of TCZ treatment, the ESR, CRP, WBC, RF, PLT levels and DAS28-CRP, DAS28-ESR, synovial membrane thickness and PD score of hand joints of the patients at different time points gradually decreased, and there were significant differences between each time point (P < 0.05). At 12 weeks and 24 weeks of TCZ treatment, 43 cases (42.00%) and 54 cases (68.00%) met the ACR20 standard respectively. The area under receiver operating characteristic curve of PD score of hand joints at 12 weeks of TCZ treatment was 0.704 in predicting the ACR20 criteria at 24 weeks of TCZ treatment (P < 0.05), and the sensitivity and specificity were 0.875 and 0.529 under the Cut-off value.

  Conclusion  TCZ treatment can significantly alleviate the inflammatory response, reduce the disease activity and the joint synovial damages in patients with moderate to severe RA. The PD score of hand joints at 12 weeks of treatment can be used to predict the therapeutic effects at 24 weeks of treatment.