Jandl Nico M, Kleiss Sebastian, Mussawy Haider, Beil Frank T, Hubert Jan, Rolvien Tim
Department of Trauma and Orthopaedic Surgery, Division of Orthopaedics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
Bone Joint J. 2023 Mar 15;105-B(4):373-381. doi: 10.1302/0301-620X.105B4.BJJ-2022-0628.R1.
The aim of this study was to evaluate the diagnostic accuracy of the absolute synovial polymorphonuclear neutrophil cell (PMN) count for the diagnosis or exclusion of periprosthetic joint infection (PJI) after total hip (THA) or knee arthroplasty (TKA). In this retrospective cohort study, 147 consecutive patients with acute or chronic complaints following THA and TKA were included. Diagnosis of PJI was established based on the 2018 International Consensus Meeting criteria. A total of 39 patients diagnosed with PJI (32 chronic and seven acute) and 108 patients with aseptic complications were surgically revised. Using receiver operating characteristic curves and calculating the area under the curve (AUC), an optimal synovial cut-off value of 2,000 PMN/µl was determined (AUC 0.978 (95% confidence interval (CI) 0.946 to 1)). Using this cut-off, sensitivity and specificity of absolute synovial PMN count for PJI were 97.4% (95% CI 91.2 to 100) and 93.5% (95% CI 88.9 to 98.1), respectively. Positive and negative predictive value were 84.4% (95% CI 72.7 to 93.9) and 99.0% (95% CI 96.7 to 100), respectively. Exclusion of 20 patients with acute complications improved specificity to 97.9% (95% CI 94.6 to 100). Different cut-off values for THA (< 3,600 PMN/µl) and TKA (< 2,000 PMN/µl) were identified. Absolute synovial PMN count correlated strongly with synovial alpha-defensin (AD) ( = 0.759; p < 0.001). With a positive AD result, no additional PJI could be identified in any case. Absolute synovial PMN count is a widely available, rapid, cost-effective, and accurate marker in PJI diagnostics, whereas synovial AD appears to be a surrogate parameter of absolute synovial PMN count. Despite limitations in the early postoperative phase, wear, and rheumatic diseases in confirming PJI, an absolute synovial PMN count below 2,000/µl is highly suitable for ruling out PJI, with specific cut-off values for THA and TKA.
本研究的目的是评估全髋关节置换术（THA）或膝关节置换术（TKA）后，绝对滑膜多形核中性粒细胞（PMN）计数用于诊断或排除假体周围关节感染（PJI）的诊断准确性。在这项回顾性队列研究中，纳入了147例THA和TKA术后出现急性或慢性症状的连续患者。PJI的诊断基于2018年国际共识会议标准。共有39例被诊断为PJI的患者（32例慢性和7例急性）和108例无菌性并发症患者接受了手术翻修。通过绘制受试者工作特征曲线并计算曲线下面积（AUC），确定了PMN的最佳滑膜临界值为2,000个/微升（AUC为0.978（95%置信区间（CI）为0.946至1））。采用该临界值，绝对滑膜PMN计数对PJI的敏感性和特异性分别为97.4%（95%CI为91.2至100）和93.5%（95%CI为88.9至98.1）。阳性和阴性预测值分别为84.4%（95%CI为72.7至93.9）和99.0%（95%CI为96.7至100）。排除20例急性并发症患者后，特异性提高到97.9%（95%CI为94.6至100）。确定了THA（<3,600个PMN/微升）和TKA（<2,000个PMN/微升）的不同临界值。绝对滑膜PMN计数与滑膜α-防御素（AD）密切相关（r=0.759；p<0.001）。AD结果为阳性时，在任何情况下均未发现额外的PJI病例。绝对滑膜PMN计数是PJI诊断中一种广泛可用、快速、经济高效且准确的标志物，而滑膜AD似乎是绝对滑膜PMN计数的替代参数。尽管在术后早期、磨损和风湿性疾病方面在确诊PJI存在局限性，但绝对滑膜PMN计数低于2,000个/微升非常适合排除PJI，THA和TKA有特定的临界值。
