SAT0305 PERFORMANCE OF HIGH FREQUENCY ULTRASOUND IN THE ASSESSMENT OF SKIN INVOLVEMENT IN SYSTEMIC SCLEROSIS. (13th June 2020)

• Record Type: Journal Article
• Authors: Lettieri, G.; Picerno, V.; Temiz Karadağ, D.; Padula, M. C.; Mennillo, G. A.; Padula, A.; D'angelo, S.; Abignano, G.
• Is Part Of: Annals of the rheumatic diseases. Volume 79(2020)Supplement 1
• Page Start: 1097
• Page End: 1098
• Publication Date: 2020-06-13
• Subjects: Rheumatism -- Periodicals; 616.723005
• DOI: 10.1136/annrheumdis-2020-eular.6373
• Languages: English
• ISSNs: 0003-4967

Abstract

Abstract : Background: The modified Rodnan skin score (mRSS) is the current gold standard for skin assessment in systemic sclerosis (SSc) both in clinical trials and practice. High frequency ultrasound (HFUS) has been suggested to offer a quantitative assessment of skin thickness in SSc by several studies, however results are inhomogeneous with regards to the machine used, number of imaged sites, as well as the various stages of skin involvement. Objectives: Aim of this cross-sectional study was to compare performance of HFUS in the assessment of skin involvement in diffuse cutaneous SSc (dcSSc) patients, at different disease stages, as compared with healthy controls (HC). Methods: Dorsal finger, hand, forearm and upper arm skin of consecutive dcSSc patients, at different disease stages, and of matched-HC were scanned bilaterally using HFUS. Two investigators, expert in MSK ultrasound, blinded to the clinical details, measured skin thickness using Esaote MyLab70 equipped with a 22 MHZ probe. Clinical involvement was assessed by a blinded operator using the mRSS and results were compared with imaging data. Statistical analysis was performed using GraphPad Prism software V.7.0. Results: A total of 704 HFUS images were obtained from 22 dcSSc patients [20 Female, mean age 49 (±11) years, 12 with ≤ 5 years disease duration] and 22 HC [20 Female, mean age 50.7 (±6.7) years]. Skin thickness was significantly higher in SSc patients than in HC at fingers (p<0.0001) and hands (p<0.0001), while no significant difference was found at the forearms and upper arms (p>0.05). HFUS showed a good discriminative ability between SSc and HC skin at fingers and hands (AUC 0.91, 0.81, 0.6 and 0.65 for fingers, hands, forearms and upper arms respectively). When analysing the subgroup of SSc patients with ≤5 years disease duration, HFUS showed a slightly lower performance in discriminating between SSc without clinical skin involvement (site mRSS=0) and HC (AUC 0.68, 0.57, 0.68 for hands, forearms and upper arms respectively). Mean HFUS skin thickness significantly correlated with mRSS at site of analysis (hand: r=0.78, p=<0.0001; forearm: r=0.47, p=0.0013; upper arm: r=0.52, p=0.0003) and total mRSS (hand: r=0.53, p=0.0002; forearm: r=0.63, p<0.0001; upper arm: r=0.63, p<0.0001). No significant correlation was found between finger skin thickness and mRSS (both local and total, p>0.05). Interobserver reliability for skin thickness was good to excellent at all sites with intraclass correlation coefficient ranging between 0.79 and 0.94. Conclusion: HFUS of the skin is a reliable measure of skin involvement in SSc. Studies with higher number of patients with different clinical features are needed to explore the potential of HFUS to discriminate between healthy and SSc skin, including sites at a preclinical stage of involvement. Disclosure of Interests: None declared