Center for Orthopedics, Trauma Surgery and Sports Medicine, München Klinik Bogenhausen, Englschalkinger Str. 77, 81925, Munich, Germany.
Department of Orthopedics and Sports Orthopedics, Klinikum rechts der Isar, Technical University of Munich, Ismaninger Str. 22, 81675, Munich, Germany.
Int Orthop. 2023 Apr;47(4):929-944. doi: 10.1007/s00264-023-05691-3. Epub 2023 Jan 19.
The diagnostic criteria of prosthetic joint infection (PJI) recommended by the most commonly used diagnostic algorithms can be obscured or distorted by other inflammatory processes or aseptic pathology. Furthermore, the most reliable diagnostic criteria are garnered during revision surgery. A robust, reliable addition to the preoperative diagnostic cascade is warranted. Calprotectin has been shown to be an excellent diagnostic marker for PJI. In this study, we aimed to evaluate a lateral flow test (LFT) in the challenging patient cohort of a national referral centre for revision arthroplasty.
Beginning in March 2019, we prospectively included patients scheduled for arthroplasty exchange of a total hip (THA) or knee arthroplasty (TKA). Synovial fluid samples were collected intra-operatively. We used the International Consensus Meeting of 2018 (ICM) score as the gold standard. We then compared the pre-operative ICM score with the LFT result to calculate its diagnostic accuracy as a standalone pre-operative marker and in combination with the ICM score as part of an expanded diagnostic workup.
A total of 137 patients with a mean age of 67 (± 13) years with 53 THA and 84 TKA were included. Ninety-nine patients (72.8%) were not infected, 34 (25.0) were infected, and four (2.9%) had an inconclusive final score and could not be classified after surgery. The calprotectin LFT had a sensitivity (95% confidence interval) of 0.94 (0.80-0.99) and a specificity of 0.87 (0.79-0.93). The area under the receiver operating characteristic curve (AUC) for the calprotectin LFT was 0.94 (0.89-0.99). In nine cases with an inconclusive pre-operative ICM score, the calprotectin LFT would have led to the correct diagnosis of PJI.
The synovial fluid calprotectin LFT shows excellent diagnostic metrics both as a rule-in and a rule-out test, even in a challenging patient cohort with cases of severe osteolysis, wear disease, numerous preceding surgeries, and poor soft tissue conditions, which can impair the common diagnostic criteria. As it is available pre-operatively, this test might prove to be a very useful addition to the diagnostic algorithm.
最常用的诊断算法推荐的人工关节感染（PJI）的诊断标准可能会被其他炎症过程或无菌性病变所掩盖或扭曲。此外，最可靠的诊断标准是在翻修手术中获得的。因此，需要在术前诊断级联中增加一个强大、可靠的指标。钙卫蛋白已被证明是 PJI 的一种极好的诊断标志物。在这项研究中，我们旨在评估一种侧向流动试验（LFT）在全国关节翻修中心的具有挑战性的患者群体中的应用。
从 2019 年 3 月开始，我们前瞻性地纳入了计划进行全髋关节置换术（THA）或膝关节置换术（TKA）翻修的患者。术中采集滑膜液样本。我们以 2018 年国际共识会议（ICM）评分作为金标准。然后，我们将术前 ICM 评分与 LFT 结果进行比较，以计算其作为单独的术前标志物的诊断准确性，并与 ICM 评分结合作为扩展诊断评估的一部分。
共纳入 137 例患者，平均年龄 67（±13）岁，其中 53 例为 THA，84 例为 TKA。99 例（72.8%）患者未感染，34 例（25.0%）患者感染，4 例（2.9%）患者最终评分不确定，手术后无法分类。钙卫蛋白 LFT 的灵敏度（95%置信区间）为 0.94（0.80-0.99），特异性为 0.87（0.79-0.93）。钙卫蛋白 LFT 的受试者工作特征曲线（ROC）下面积为 0.94（0.89-0.99）。在 9 例术前 ICM 评分不确定的病例中，钙卫蛋白 LFT 可正确诊断 PJI。
即使在严重骨溶解、磨损性疾病、多次手术和软组织状况较差的具有挑战性的患者群体中，滑膜液钙卫蛋白 LFT 作为一种确诊和排除诊断的测试，其诊断指标均表现出极佳的准确性。由于它可以在术前获得，因此该测试可能成为诊断算法中非常有用的补充。
