Abstract
IntroductionCalprotectin (MRP8/MRP14, S100A8/A9) is associated with disease activity in patients with rheumatoid arthritis (RA). Ultrasonography (US) is a reliable method for evaluation of synovitis (B-mode (BM) and power Doppler (PD)). The present objectives were to explore in RA patients the associations between calprotectin and a comprehensive US examination, as well as the responsiveness of calprotectin compared to other inflammatory markers during anti-TNF treatment.MethodsA total of 20 RA patients starting treatment with adalimumab were examined longitudinally by US (BM and PD (semi-quantitative scores 0 to 3) of 78 joints, 36 tendons/tendon groups and 2 bursae) and clinically at baseline and after 1, 3, 6 and 12 months. Associations between the US sum scores and the inflammatory markers calprotectin, serum amyloid A (SAA), CRP and ESR were explored by correlation and linear regression analyses, and the response to treatment was assessed by Standardized Response Mean (SRM).ResultsThe inflammatory markers, clinical examinations and US sum scores improved during treatment (P < 0.001). Of the inflammatory markers, calprotectin had the highest correlation coefficients with the total BM and PD sum scores (median (range) 0.59 (0.37 to 0.76) for BM and 0.56 (0.38 to 0.72) for PD). Even higher correlations were found between calprotectin and sum US scores of reduced number of joint counts. Calprotectin made a considerable contribution to total US sum scores in the linear regression analyses (P = 0.001 to 0.031) and among the inflammatory markers, calprotectin had the highest SRM (0.84 at one month).ConclusionsCalprotectin was associated with the sum scores from a comprehensive US assessment and was responsive to change during anti-TNF treatment. Thus, examination of this leukocyte protein could be of additional value in the assessment of RA patients on biologic treatment.
Highlights
Calprotectin (MRP8/MRP14, S100A8/A9) is associated with disease activity in patients with rheumatoid arthritis (RA)
To assess the validity of the US examination, the 28 joints included in the disease activity score (DAS28) were explored for similarity in detecting arthritis by correlating the number of joints identified by clinical evaluation of swelling and B-mode or grey scale (BM) score (≥ 1 vs. 0)
The present study indicates that calprotectin levels are associated with the overall inflammation in RA patients, including both the amount of synovial hypertrophy explored by BM and the extent of vascularization evaluated by power Doppler (PD)
Summary
Calprotectin (MRP8/MRP14, S100A8/A9) is associated with disease activity in patients with rheumatoid arthritis (RA). Assessment of inflammatory activity is of pivotal importance for the optimal treatment of patients with rheumatoid arthritis (RA). The extent of synovitis is usually scored semi-quantitatively (scale 0 to 3) both for grey scale (or B-mode (BM)) synovitis (including combined evaluation of synovial hypertrophy and effusion) and power Doppler (PD) vascularization, and the US scores have been shown to be sensitive for improvement during biological treatment in RA patients [17,18,19,20]. There is no consensus on the optimal number of joints and tendons to be assessed for US evaluation of inflammatory activity in RA patients, but similar sensitivity to change has been found for US examinations of different combinations of joints and tendons during biological treatment [22]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
