Reliability assessment of ultrasound muscle echogenicity in patients with rheumatic diseases: Results of a multicenter international web-based study

ObjectivesTo investigate the inter/intra-reliability of ultrasound (US) muscle echogenicity in patients with rheumatic diseases.MethodsForty-two rheumatologists and 2 radiologists from 13 countries were asked to assess US muscle echogenicity of quadriceps muscle in 80 static images and 20 clips from 64 patients with different rheumatic diseases and 8 healthy subjects. Two visual scales were evaluated, a visual semi-quantitative scale (0–3) and a continuous quantitative measurement (“VAS echogenicity,” 0–100). The same assessment was repeated to calculate intra-observer reliability. US muscle echogenicity was also calculated by an independent research assistant using a software for the analysis of scientific images (ImageJ). Inter and intra reliabilities were assessed by means of prevalence-adjusted bias-adjusted Kappa (PABAK), intraclass correlation coefficient (ICC) and correlations through Kendall’s Tau and Pearson’s Rho coefficients.ResultsThe semi-quantitative scale showed a moderate inter-reliability [PABAK = 0.58 (0.57–0.59)] and a substantial intra-reliability [PABAK = 0.71 (0.68–0.73)]. The lowest inter and intra-reliability results were obtained for the intermediate grades (i.e., grade 1 and 2) of the semi-quantitative scale. “VAS echogenicity” showed a high reliability both in the inter-observer [ICC = 0.80 (0.75–0.85)] and intra-observer [ICC = 0.88 (0.88–0.89)] evaluations. A substantial association was found between the participants assessment of the semi-quantitative scale and “VAS echogenicity” [ICC = 0.52 (0.50–0.54)]. The correlation between these two visual scales and ImageJ analysis was high (tau = 0.76 and rho = 0.89, respectively).ConclusionThe results of this large, multicenter study highlighted the overall good inter and intra-reliability of the US assessment of muscle echogenicity in patients with different rheumatic diseases

Prevalence and distribution of cartilage and bone damage at metacarpal head in healthy subjects

Objectives: To determine the prevalence and distribution of the ultrasound (US) findings indicating cartilage and bone damage at the metacarpal head (MH) in a group of healthy subjects (HS), and their association with the clinical and US data. We also aimed to provide standard reference values of cartilage thickness. Methods: US scans of the dorsal aspect of the metacarpophalangeal joints (MCPj) from 2nd to 5th finger of both hands were performed in 179 HS. The presence of cartilage damage, osteophytes and bone erosions was recorded. Results: Cartilage damage, osteophytes and bone erosions were found in at least one MCPj in 30 (16.8%), 17 (9.5%) and 4 (2.2%) out of 179 HS, respectively. Signs of cartilage damage were found in 91 out of 1432 MHs (6.4%). Blurring of the chondrosynovial margin, minimal and severe thinning were detected in 73.7%, 26.3% and 0% of the 91 MHs, respectively. Osteophytes and bone erosions were found in 31 (2.2%) and in 4 (0.3%) MCPjs. The thickness of the MH cartilage ranged between 0.41 and 1.10 mm in males and between 0.36 and 1.03 mm in females. A significant association was found between cartilage thickness and age (r=-0.33, p<0.001), sex (rpb=0.42, p<0.001), height (r=0.39, p<0.001) and osteophytes in the same joint (v=-0.54, p<0.001) and between working condition and osteophytes (v=0.31, p=0.021). Conclusions: This cross-sectional study reports the prevalence of US findings of joint damage in a large cohort of HS. Moreover, standard reference values of the MH cartilage thickness in HS are provided

Relationship between serum calprotectin (S100A8/9) and clinical, laboratory and ultrasound parameters of disease activity in rheumatoid arthritis: A large cohort study

<div><p>Background</p><p>Calprotectin may be a sensitive biomarker of rheumatoid arthritis (RA) disease activity.</p><p>Objectives</p><p>In the current study, we investigated whether calprotectin is a better biomarker than CRP for predicting clinical activity and ultrasound parameters in patients with RA.</p><p>Methods</p><p>A total of 160 patients with RA underwent clinical (swollen joint count—SJC, tender joint count—TJC, Disease Activity Score—DAS28, Clinical Disease Activity Index—CDAI, and simplified Disease Activity Index—SDAI) and ultrasound (German US7) examination. Clinical and laboratory measures were correlated with ultrasound findings using Spearman´s correlation coefficient. Differences in serum calprotectin levels in patients with variable disease activity according to the DAS28-ESR and CDAI scores were assessed using ANOVA. Multivariate regression analysis was used to determine the predictive values of calprotectin, CRP and SJC for CDAI and PD US synovitis scores.</p><p>Results</p><p>Serum calprotectin was significantly associated with DAS28-ESR (r = 0.321, p<0.001), DAS28-CRP (r = 0.346, p<0.001), SDAI (r = 0.305, p<0.001), CDAI (r = 0.279, p<0.001) scores and CRP levels (r = 0.556, p<0.001). Moreover, calprotectin was significantly correlated with GS (r = 0.379, p<0.001) and PD synovitis scores (r = 0.419, p<0.001). The multivariate regression analysis showed that calprotectin is a better predictor of the CDAI score and PD US synovitis than CRP.</p><p>Conclusions</p><p>The results of this study support an additional role of calprotectin in assessing inflammatory activity in patients with RA.</p></div

Receiver-operator characteristic curves of serum calprotectin and CRP for distinguishing patients with ultrasound remission from those with subclinical ultrasound activity.

<p>All the patients achieved clinical remission according to a) DAS28-ESR, b) DAS28-CRP, c) SDAI and d) CDAI criteria.</p

Box plots showing the associations between calprotectin serum levels and disease activity according to A) DAS28-ESR, B) DAS28-CRP, C) SDAI, and D) CDAI.

<p>Box plots showing the associations between calprotectin serum levels and disease activity according to A) DAS28-ESR, B) DAS28-CRP, C) SDAI, and D) CDAI.</p

Baseline characteristics of the patients with rheumatoid arthritis.

<p>Baseline characteristics of the patients with rheumatoid arthritis.</p