Serum calprotectin (S100A8/9): an independent predictor of ultrasound synovitis in patients with rheumatoid arthritis

Abstract

IntroductionCalprotectin, a heterodimeric complex of S100A8/9 (MRP8/14), has been proposed as an important serum biomarker that reflects disease activity and structural joint damage in rheumatoid arthritis (RA). The objective of this cross-sectional study was to test the hypothesis that calprotectin is associated with clinical and ultrasound-determined disease activity in patients with RA.MethodsA total of 37 patients with RA (including 24 females, a mean disease duration of 20 months) underwent a clinical examination and 7-joint ultrasound score (German US-7) of the clinically dominant hand and foot to assess synovitis by grey-scale (GS) and synovial vascularity by power Doppler (PD) ultrasound using semiquantitative 0–3 grading. The levels of serum calprotectin and C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) were determined at the time of the ultrasound assessment. We analysed the relationship between serum calprotectin level, traditional inflammatory markers, and ultrasound-determined synovitis.ResultsThe levels of serum calprotectin were significantly correlated with swollen joint count (r = 0.465, p < 0.005), DAS28-ESR (r = 0.430, p < 0.01), ESR (r = 0.370, p < 0.05) and, in particular, CRP (r = 0.629, p < 0.001). Calprotectin was significantly associated with GS (r = 0.359, p < 0.05) and PD synovitis scores (r = 0.497, p < 0.005). Using multivariate regression analysis, calprotectin, adjusted for age and sex, was a better predictor of PD synovitis score (R2 = 0.765, p < 0.001) than CRP (R2 = 0.496, p < 0.001).ConclusionsThe serum levels of calprotectin are significantly associated with clinical, laboratory and ultrasound assessments of RA disease activity. These results suggest that calprotectin might be superior to CRP for monitoring ultrasound-determined synovial inflammation in RA patients.

Serum Calprotectin Discriminates Subclinical Disease Activity from Ultrasound-Defined Remission in Patients with Rheumatoid Arthritis in Clinical Remission

“…The ultrasonographers were blinded to each patient’s clinical examination and laboratory findings. The inter- and intra-observer reliability was moderate to very good, as shown in a recent study [27]. …”

“…Recently, we demonstrated an association between serum calprotectin and clinical and laboratory markers of disease activity and, more relevantly, with ultrasound synovitis, which is generally considered to be more precise in the evaluation of joint inflammation [27]. Moreover, we found that serum calprotectin might be a better predictor of ultrasound-determined synovitis than CRP [27].…”

“…Recently, a significant correlation between calprotectin and ultrasound-determined synovial inflammation was demonstrated in RA patients [26]. We have shown that calprotectin might be a more sensitive tool for assessing joint inflammation and a better predictor of ultrasound synovitis than conventionally used C-reactive protein (CRP) [27]. Thus, we suggested that calprotectin and musculoskeletal ultrasonography might provide more reliable tools for evaluating joint inflammatory activity in RA patients.…”

Evaluation of Serum S100A8/S100A9 Levels in Patients with Autoimmune Thyroid Diseases

“…In rheumatoid arthritis, it increases during the acute phase of the disease, decreases after treatment, and is more sensitive than the hepatic-originated classic acute phase proteins (11)(12). In AITD, which is also associated with inflammation, serum S100A8/S100A9 levels have not yet been determined.…”

The 2014 ACR annual meeting: a bird’s eye view of autoimmunity in 2015

“…Calprotectin derives predominantly from neutrophils and monocytes and was previously reported to be associated with structural joint damage in psoriatic arthritis (PsA) and RA [45]. Jana Hurnakova and Colleagues investigated serum calprotectin levels in 37 patients with RA [46] and reported that calprotectin levels significantly correlate with DAS28 (r=0.385, p<0.05), CRP (r=0.629, p<0.001), and swollen joint count (r=0.465, p<0.005). In addition, calprotectin is significantly associated with the findings in gray-scale and power A C C E P T E D M A N U S C R I P T…”