Arunrukthavon Piti, Heebthamai Danai, Benchasiriluck Prapasri, Chaluay Supinda, Chotanaphuti Thanainit, Khuangsirikul Saradej
Department of Orthopedic Surgery, Phramongkutklao Hospital and College of Medicine, Bangkok, Thailand.
Department of Orthopedic Surgery, Queen Savang Vadhana Memorial Hospital, Sriracha, Chonburi, Thailand.
Arthroplasty. 2020 Feb 10;2(1):6. doi: 10.1186/s42836-020-0024-2.
Early diagnosis of knee osteoarthritis (OA) remains a diagnostic challenge. Urinary C-terminal cross-linked telopeptide of type II collagen (urinary CTX-II) is one of the potential OA biomarkers. However, conclusive evidence regarding the use of this biomarker as a tool for early diagnosis is still lacking. The purposes of this study were to compare urinary CTX-II levels in patients with knee OA and in healthy controls, to evaluate the correlation between urinary CTX-II levels, radiographic severity of OA, and patient-reported outcomes and to evaluate the effect of age and gender on urinary CTX-II levels in the Asian populations.
Two groups were studied. The OA group included 78 patients with knee OA aged > 40 years who met the diagnostic criteria for knee OA described by the American College of Rheumatology (ACR). The control group consisted of 51 healthy participants age > 40 years without clinical or radiographic evidence of knee OA. Bilateral knee radiographs were taken and classified according to the Kellgren and Lawrence (KL) grading system. Urinary CTX-II was measured using a competitive ELISA test and Western Ontario and Mcmaster Universities Arthritis Index (WOMAC) was also recorded in all participants.
Urinary CTX-II was significantly higher in the OA group than in the control group (p < 0.001). The severe knee OA group (KL grade 3 and 4) had higher urinary CTX-II levels than mild knee OA group (KL grade 2) but the difference did not reach statistical significance (p = 0.2). There was a moderate correlation between urinary CTX-II levels and KL grades (r = 0.405, p < 0.001) and a weak correlation between urinary CTX-II levels and WOMAC index scores (r = 0.367, p < 0.001). Multiple regression analysis showed that urinary CTX-II was independently associated with KL grades. Whereas age, gender, and WOMAC index had no statistically significant influence on the urinary CTX-II levels.
Patients with knee OA had higher urinary CTX-II levels than healthy controls. Moreover, levels of urinary CTX-II were independently correlated with radiographic severity of knee OA. Age, gender, and patient-reported outcomes exerted no effect on the urinary CTX-II levels.
Diagnostic Level III.
膝关节骨关节炎（OA）的早期诊断仍然是一项诊断挑战。尿Ⅱ型胶原C端交联肽（尿CTX-II）是潜在的OA生物标志物之一。然而，关于将该生物标志物用作早期诊断工具的确凿证据仍然缺乏。本研究的目的是比较膝关节OA患者和健康对照者的尿CTX-II水平，评估尿CTX-II水平、OA的放射学严重程度和患者报告结局之间的相关性，并评估年龄和性别对亚洲人群尿CTX-II水平的影响。
研究了两组。OA组包括78例年龄>40岁且符合美国风湿病学会（ACR）描述的膝关节OA诊断标准的膝关节OA患者。对照组由51名年龄>40岁、无膝关节OA临床或放射学证据的健康参与者组成。拍摄双侧膝关节X线片，并根据Kellgren和Lawrence（KL）分级系统进行分类。使用竞争性ELISA试验测量尿CTX-II，并记录所有参与者的西安大略和麦克马斯特大学关节炎指数（WOMAC）。
OA组的尿CTX-II显著高于对照组（p<0.001）。重度膝关节OA组（KL 3级和4级）的尿CTX-II水平高于轻度膝关节OA组（KL 2级），但差异无统计学意义（p=0.2）。尿CTX-II水平与KL分级之间存在中度相关性（r=0.405，p<0.001），尿CTX-II水平与WOMAC指数评分之间存在弱相关性（r=0.367，p<0.001）。多元回归分析表明，尿CTX-II与KL分级独立相关。而年龄、性别和WOMAC指数对尿CTX-II水平无统计学显著影响。
膝关节OA患者的尿CTX-II水平高于健康对照者。此外，尿CTX-II水平与膝关节OA的放射学严重程度独立相关。年龄、性别和患者报告结局对尿CTX-II水平无影响。
诊断性III级。
