Department of Orthopedics and Rheumoorthopedics, Centre of Postgraduate Medical Education, Otwock, Poland.
Department of Orthopedics, Centre of Postgraduate Medical Education, Otwock, Poland.
Bone Joint J. 2021 Jan;103-B(1):46-55. doi: 10.1302/0301-620X.103B1.BJJ-2020-0953.R1.
Calprotectin (CLP) is produced in neutrophils and monocytes and released into body fluids as a result of inflammation or infection. The aim of this study was to evaluate the utility of blood and synovial CLP in the diagnosis of chronic periprosthetic joint infection (PJI).
Blood and synovial fluid samples were collected prospectively from 195 patients undergoing primary or revision hip and knee arthroplasty. Patients were divided into five groups: 1) primary total hip and knee arthroplasty performed due to idiopathic osteoarthritis (OA; n = 60); 2) revision hip and knee arthroplasty performed due to aseptic failure of the implant (AR-TJR; n = 40); 3) patients with a confirmed diagnosis of chronic PJI awaiting surgery (n = 45); 4) patients who have finished the first stage of the PJI treatment with the use of cemented spacer and were qualified for replantation procedure (SR-TJR; n = 25), and 5) patients with rheumatoid arthritis undergoing primary total hip and knee arthroplasty (RA; n = 25). CLP concentrations were measured quantitatively in the blood and synovial fluid using an immunoturbidimetric assay. Additionally, blood and synovial CRP, blood interleukin-6 (IL-6), and ESR were measured, and a leucocyte esterase (LE) strip test was performed.
Patients with PJI had higher CLP concentrations than those undergoing aseptic revision in blood (median PJI 2.14 mg/l (interquartile range (IQR) 1.37 to 3.56) vs AR-TJR 0.66 mg/l (IQR 0.3 to 0.83); p < 0.001) and synovial fluid samples (median PJI 20.46 mg/l (IQR 14.3 to 22.36) vs AR-TJR 0.7 mg/l (IQR 0.41 to 0.95); p < 0.001). With a cut-off value of 1.0 mg/l, blood CLP showed a sensitivity, specificity, positive predictive value, and negative predictive value of 93.3%, 87.5%, 89.4%, and 92.1%, respectively. For synovial fluid with a cut-off value of 1.5 mg/l, these were 95.6%, 95%, 95.5%, and 95%, respectively.
This small study suggests that synovial and blood CLP are useful markers in chronic PJI diagnosis with similar or higher sensitivity and specificity than routinely used markers such as CRP, ESR, IL-6, and LE. CLP was not useful to differentiate patients with PJI from those with rheumatoid arthritis. Cite this article: 2021;103-B(1):46-55.
钙卫蛋白（CLP）由中性粒细胞和单核细胞产生，并在炎症或感染时释放到体液中。本研究旨在评估血液和滑液 CLP 在诊断慢性人工关节假体周围感染（PJI）中的作用。
前瞻性收集了 195 例行初次或翻修髋关节和膝关节置换术的患者的血液和滑膜液样本。患者分为五组：1）特发性骨关节炎（OA；n=60）行初次全髋关节和膝关节置换术；2）因假体无菌性失败（AR-TJR；n=40）行翻修髋关节和膝关节置换术；3）确诊为慢性 PJI 并等待手术（n=45）；4）已完成使用骨水泥间隔器的 PJI 第一阶段治疗且有资格进行再植手术（SR-TJR；n=25）；5）类风湿关节炎行初次全髋关节和膝关节置换术（RA；n=25）。采用免疫比浊法定量检测血液和滑膜液中的 CLP 浓度。同时，检测血液和滑膜 C 反应蛋白（CRP）、血液白细胞介素 6（IL-6）和红细胞沉降率（ESR），并进行白细胞酯酶（LE）条带试验。
与无菌翻修相比，PJI 患者的血液（中位数 PJI 2.14mg/l（IQR 1.37 至 3.56）vs AR-TJR 0.66mg/l（IQR 0.3 至 0.83）；p＜0.001）和滑膜液样本（中位数 PJI 20.46mg/l（IQR 14.3 至 22.36）vs AR-TJR 0.7mg/l（IQR 0.41 至 0.95）；p＜0.001）中的 CLP 浓度更高。以 1.0mg/l 为截断值，血液 CLP 的灵敏度、特异性、阳性预测值和阴性预测值分别为 93.3%、87.5%、89.4%和 92.1%。以 1.5mg/l 为截断值时，滑膜液的灵敏度、特异性、阳性预测值和阴性预测值分别为 95.6%、95%、95.5%和 95%。
本小样本研究表明，滑液和血液 CLP 是慢性 PJI 诊断的有用标志物，其灵敏度和特异性与 CRP、ESR、IL-6 和 LE 等常用标志物相似或更高。CLP 对区分 PJI 患者与类风湿关节炎患者没有帮助。
2021；103-B（1）：46-55。
