Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts.
Department of Orthopaedic Surgery, Newton-Wellesley Hospital, Newton, Massachusetts.
J Arthroplasty. 2023 Sep;38(9):1854-1860. doi: 10.1016/j.arth.2023.03.010. Epub 2023 Mar 17.
Diagnosing periprosthetic joint infection (PJI) following total knee arthroplasty (TKA) remains challenging despite recent advancements in testing and evolving criteria over the last decade. Moreover, the effects of antibiotic use on diagnostic markers are not fully understood. Thus, this study sought to determine the influence of antibiotic use within 48 hours before knee aspiration on synovial and serum laboratory values for suspected late PJI.
Patients who underwent a TKA and subsequent knee arthrocentesis for PJI workup at least 6 weeks after their index arthroplasty were reviewed across a single healthcare system from 2013 to 2020. Median synovial white blood cell (WBC) count, synovial polymorphonuclear (PMN) percentage, serum erythrocyte sedimentation rate (ESR), serum C-reactive protein (CRP), and serum WBC count were compared between immediate antibiotic and nonantibiotic PJI groups. Receiver operating characteristic (ROC) curves and Youden's index were used to determine test performance and diagnostic cutoffs for the immediate antibiotics group.
The immediate antibiotics group had significantly more culture-negative PJIs than the no antibiotics group (38.1 versus 16.2%, P = .0124). Synovial WBC count demonstrated excellent discriminatory ability for late PJI in the immediate antibiotics group (area under curve, AUC = 0.97), followed by synovial PMN percentage (AUC = 0.88), serum CRP (AUC = 0.86), and serum ESR (AUC = 0.82).
Antibiotic use immediately preceding knee aspiration should not preclude the utility of synovial and serum lab values for the diagnosis of late PJI. Instead, these markers should be considered thoroughly during infection workup considering the high rate of culture-negative PJI in these patients.
Level III, retrospective comparative study.
尽管过去十年中在检测和不断发展的标准方面取得了进展，但在全膝关节置换术（TKA）后诊断假体周围关节感染（PJI）仍然具有挑战性。此外，抗生素的使用对诊断标志物的影响尚未完全了解。因此，本研究旨在确定在膝关节抽吸前 48 小时内使用抗生素对疑似晚期 PJI 的关节滑液和血清实验室值的影响。
对 2013 年至 2020 年期间在单一医疗保健系统中接受 TKA 并随后进行膝关节抽吸以评估 PJI 的患者进行了回顾性研究。比较了即时抗生素和非抗生素 PJI 组之间的关节滑液白细胞（WBC）计数中位数、关节滑液多形核（PMN）百分比、血清红细胞沉降率（ESR）、血清 C 反应蛋白（CRP）和血清 WBC 计数。使用接收者操作特征（ROC）曲线和 Youden 指数来确定即时抗生素组的测试性能和诊断截止值。
即时抗生素组的培养阴性 PJI 明显多于非抗生素组（38.1%比 16.2%，P=.0124）。在即时抗生素组中，关节滑液 WBC 计数对晚期 PJI 具有出色的鉴别能力（曲线下面积，AUC=0.97），其次是关节滑液 PMN 百分比（AUC=0.88）、血清 CRP（AUC=0.86）和血清 ESR（AUC=0.82）。
在膝关节抽吸前立即使用抗生素不应排除关节滑液和血清实验室值在诊断晚期 PJI 中的作用。相反，在这些患者中，由于培养阴性 PJI 的发生率较高，因此在感染评估期间应充分考虑这些标志物。
III 级，回顾性比较研究。
