Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Purdue University, 625 Harrison St., West Lafayette, IN, USA.
Department of Statistics, School of Science, Purdue University, West Lafayette, IN, USA.
Osteoarthritis Cartilage. 2020 Feb;28(2):231-238. doi: 10.1016/j.joca.2019.10.006. Epub 2019 Nov 1.
To evaluate infrared (IR) spectroscopy of serum as a screening tool to differentiate dogs affected by naturally occurring osteoarthritis (OA) associated with cranial cruciate ligament rupture (CrCLR) and controls.
104 adult dogs with CrCLR (affected group) and 50 adult control dogs were recruited for this prospective observational study. Serum samples were collected preoperatively from CrCLR dogs and from a subset of these dogs at 4-, and 12-week post-surgical intervention to stabilize the affected stifles. Serum was collected once from control dogs. Dry films were made from serum samples, and IR absorbance spectra acquired. Data preprocessing, principal component analysis and multivariate analysis of covariance were performed to separate samples from the two groups, and to evaluate temporal differences. Weighted logistic regression with L1 regularization method was used to develop a predictive model. Model performance based on an independent test set was evaluated.
Spectral data analysis revealed significant separation between the sera of CrCLR and control dogs (P < 0.0001), but not amongst different time points in the OA group. The sensitivity, specificity, AUC and accuracy of the test set were 84.62%, 96.15%, 93.20% and 92.31% respectively.
These findings confirm the potential of IR-spectroscopy of serum with chemometrics methods to differentiate controls from dogs with OA associated with CrCLR. This is the first step in development of an economic, and comparatively simple IR-based screening serum test for OA. Utility of this tool as a clinical screening and diagnostic test requires further investigation and validation.
评估血清中的红外（IR）光谱作为一种筛选工具，以区分患有与十字韧带断裂（CrCLR）相关的自然发生的骨关节炎（OA）的狗和对照狗。
本前瞻性观察研究纳入了 104 只患有 CrCLR 的成年狗（受影响组）和 50 只成年对照狗。从 CrCLR 狗术前以及这些狗中的一部分在手术后 4 周和 12 周稳定受影响的膝关节时采集血清样本。从对照组狗采集一次血清样本。从血清样本中制备干胶片，并获取 IR 吸收光谱。进行数据预处理、主成分分析和协方差的多元分析，以分离两组样本，并评估时间差异。使用带 L1 正则化方法的加权逻辑回归来开发预测模型。基于独立测试集评估模型性能。
光谱数据分析显示，CrCLR 和对照狗的血清之间存在显著分离（P < 0.0001），但 OA 组在不同时间点之间没有分离。测试集的敏感性、特异性、AUC 和准确性分别为 84.62%、96.15%、93.20%和 92.31%。
这些发现证实了采用化学计量学方法对血清进行 IR 光谱分析可以区分对照狗和与 CrCLR 相关的 OA 狗的潜力。这是开发经济且相对简单的基于 IR 的 OA 筛选血清测试的第一步。该工具作为临床筛选和诊断测试的实用性需要进一步的研究和验证。
