V.A. Flower, Consultant Rheumatologist, MBBS, PhD, J.D. Pauling, Consultant Rheumatologist and Senior Lecturer, BMBS, PhD, Department of Rheumatology, Royal National Hospital for Rheumatic Diseases, Royal United Hospitals NHS Foundation Trust, Bath, Department of Pharmacy and Pharmacology, University of Bath, Bath;
S.L. Barratt, BMBS, PhD, Department of Respiratory Medicine, North Bristol NHS Trust, Bristol, Academic Respiratory Unit, School of Clinical Sciences, University of Bristol, Bristol.
J Rheumatol. 2021 Jun;48(6):867-876. doi: 10.3899/jrheum.200234. Epub 2020 Nov 1.
The modified Rodnan skin score (mRSS) remains the preferred method for skin assessment in systemic sclerosis (SSc). There are concerns regarding high interobserver variability of mRSS and negative clinical trials utilizing mRSS as the primary endpoint. High-frequency ultrasound (HFUS) allows objective assessment of cutaneous fibrosis in SSc. We investigated the relationship between HFUS with both mRSS and dermal collagen.
Skin thickness (ST), echogenicity, and novel shear wave elastography (SWE) were assessed in 53 patients with SSc and 15 healthy controls (HCs) at the finger, hand, forearm, and abdomen. The relationship between HFUS parameters with mRSS (n = 53) and dermal collagen (10 patients with SSc and 10 HCs) was investigated. Intraobserver repeatability of HFUS was calculated using intraclass correlation coefficients (ICCs).
HFUS assessment of ST (hand/forearm) and SWE (finger/hand) correlated with local mRSS at some sites. Subclinical abnormalities in ST, echogenicity, and SWE were present in clinically uninvolved SSc skin. Additionally, changes in echogenicity and SWE were sometimes apparent despite objectively normal ST on HFUS. ST, SWE, and local mRSS correlated strongly with collagen quantification (r = 0.697, 0.709, 0.649, respectively). Intraobserver repeatability was high for all HFUS parameters (ICCs for ST = 0.946-0.978; echogenicity = 0.648-0.865; and SWE = 0.953-0.973).
Our data demonstrate excellent reproducibility and reassuring convergent validity with dermal collagen content. Detection of subclinical abnormalities is an additional benefit of HFUS. The observed correlations with collagen quantification support further investigation of HFUS as an alternative to mRSS in clinical trial settings.
改良的罗德南皮肤评分（mRSS）仍然是系统性硬化症（SSc）皮肤评估的首选方法。人们担心 mRSS 的观察者间变异性高，并且以 mRSS 作为主要终点的临床试验结果为阴性。高频超声（HFUS）可客观评估 SSc 皮肤纤维化。我们研究了 HFUS 与 mRSS 和真皮胶原之间的关系。
对 53 例 SSc 患者和 15 例健康对照者（HCs）的手指、手、前臂和腹部进行皮肤厚度（ST）、回声和新型剪切波弹性成像（SWE）评估。研究了 HFUS 参数与 mRSS（n=53）和真皮胶原（10 例 SSc 患者和 10 例 HCs）之间的关系。采用组内相关系数（ICCs）计算 HFUS 的观察者内重复性。
手部/前臂的 HFUS 评估 ST 和手指/手部的 SWE 与局部 mRSS 相关。在临床无受累的 SSc 皮肤中存在 ST、回声和 SWE 的亚临床异常。此外，尽管 HFUS 上的 ST 客观正常，但回声和 SWE 的变化有时仍然明显。ST、SWE 和局部 mRSS 与胶原定量高度相关（r=0.697、0.709、0.649）。所有 HFUS 参数的观察者内重复性均较高（ST 的 ICC 为 0.946-0.978；回声为 0.648-0.865；SWE 为 0.953-0.973）。
我们的数据显示 HFUS 具有出色的可重复性和令人放心的与真皮胶原含量的收敛效度。检测亚临床异常是 HFUS 的另一个益处。与胶原定量的观察相关性支持进一步研究 HFUS 作为临床试验中替代 mRSS 的方法。
