Background EULAR recommendations for the use of imaging of the joints in the clinical management of rheumatoid arthritis (RA) states that inflammation seen on ultrasound (US) is considered to be useful in monitoring disease activity, however, the timing of US assessments and the evaluation system still remain to be elucidated in daily clinical practice.
Objectives We have evaluated the therapeutic responsiveness of US variables in RA patients treated with biologic DMARDs in relation with clinical disease activity.
Methods The consecutive forty RA patients treated with biologic DMARDs, whose median disease duration 45 months and DAS28-ESR 5.34 at entry, were retrospectively recruited in the present study. Patients gave their informed consent to be subjected to the protocol. Articular synovitis was assessed by US at the 22 joints including bilateral wrist joints, 1-5th metacarpophalangeal (MCP) joints, interphalangeal joints and 2nd - 5th proximal interphalangeal (PIP) joints. Each joint was scored for gray scale (GS) as well as power Doppler (PD) on the scale from 0 to 3 and the sum of GS or PD scores was considered as US disease activity. We have investigated the correlations of the changes of US disease activity at 3 months with DAS28-EULAR response criteria at 6 months. The changes of US disease activity was set as % changes of GS or PD scores at 3 months.
Results As a whole, GS scores as well as PD scores were significantly decreased by biologic DMARDs at 3 months (p<0.0001, Wilcoxon's signed rank test). Accordingly, the % changes of both GS and PD scores at 3 months were significantly higher in moderate and good responders at 6 months than no responders (p<0.0001, Mann-Whitney's U test). Regarding to individual sites, it is interesting to note that the % changes of PD scores of wrist joints or MCP joints (sum of 1-5th MCP joints) at 3 months are most predictive toward moderate and good responders at 6 months.
Conclusions The responsiveness of US disease activities is considered to predict further clinical response in patients with RA treated by biologic DMARDs. In addition, the evaluation of wrist and MCP joints by PD may be more useful to monitor the disease activities of these patients.
Kawashiri SY, et al. Ultrasonographic examination of rheumatoid arthritis patients who are free of physical synovitis: power Doppler subclinical synovitis is associated with bone erosion. Rheumatology (Oxford). In press.
Kawashiri SY, et al. The power Doppler ultrasonography score from 24 synovial sites or 6 simplified synovial sites, including the metacarpophalangeal joints, reflects the clinical disease activity and level of serum biomarkers in patients with rheumatoid arthritis. Rheumatology (Oxford) 2011; 50: 962-5.
Disclosure of Interest None declared