Rubin Institute for Advanced Orthopedics, Center for Joint Preservation and Reconstruction, Sinai Hospital of Baltimore, 2401 West Belvedere Avenue, Baltimore, MD 21215, USA.
Clin Orthop Relat Res. 2010 Sep;468(9):2387-91. doi: 10.1007/s11999-009-1216-9.
The utility of Gram stains in diagnosing periprosthetic infections following total hip arthroplasty has recently been questioned. Several studies report low sensitivity of the test, and its poor ability to either confirm or rule out infection in patients undergoing revision total hip arthroplasty. Despite this, many institutions including that of the senior author continue to perform Gram stains during revision total hip arthroplasty.
QUESTIONS/PURPOSES: We assessed the sensitivity, specificity, accuracy, and positive and negative predictive values of Gram stains from surgical-site samplings taken from procedures on patients with both infected and aseptic revision total hip arthroplasties.
A review was performed on patients who underwent revision total hip arthroplasty between 2000 and 2007. Eighty-two Gram stains were performed on patients who had infected total hip arthroplasties and underwent revision procedures. Additionally, of the 410 revision total hip arthroplasties performed on patients who were confirmed infection-free, 120 Gram stains were performed. Patients were diagnosed as infected using multiple criteria at the time of surgery. Sensitivity, specificity, positive and negative predictive values, and accuracy were calculated from these Gram stain results.
The Gram stain demonstrated a sensitivity and specificity of 9.8% and 100%, respectively. In this series, the Gram stain had a negative predictive value of 62%, a positive predictive value of 100%, and an accuracy of 63%.
Gram stains obtained from surgical-site samples had poor sensitivity and poor negative predictive value. Based on these findings, as well as those of other authors, we believe that Gram stains should no longer be considered for diagnosing infections in revision total hip arthroplasty.
Level III, diagnostic study. See Guidelines for Authors for a complete description of levels of evidence.
最近，革兰氏染色在诊断全髋关节置换术后假体周围感染的应用受到质疑。有几项研究报告称，该检测的敏感性较低，并且在接受翻修全髋关节置换术的患者中，其确认或排除感染的能力较差。尽管如此，许多机构，包括资深作者所在的机构，在翻修全髋关节置换术中仍继续进行革兰氏染色。
问题/目的：我们评估了取自感染性和无菌性翻修全髋关节置换术患者手术部位采样的革兰氏染色的敏感性、特异性、准确性以及阳性和阴性预测值。
对 2000 年至 2007 年间接受翻修全髋关节置换术的患者进行了回顾。对患有感染性全髋关节置换术并接受翻修手术的患者进行了 82 次革兰氏染色。此外，在 410 例经证实无感染的翻修全髋关节置换术中，进行了 120 次革兰氏染色。患者在手术时根据多项标准被诊断为感染。从这些革兰氏染色结果中计算了敏感性、特异性、阳性和阴性预测值以及准确性。
革兰氏染色的敏感性和特异性分别为 9.8%和 100%。在本系列中，革兰氏染色的阴性预测值为 62%，阳性预测值为 100%，准确性为 63%。
从手术部位样本中获得的革兰氏染色敏感性和阴性预测值均较差。基于这些发现以及其他作者的研究结果，我们认为革兰氏染色不应再用于诊断翻修全髋关节置换术后的感染。
III 级，诊断研究。有关证据等级的完整描述，请参见《作者指南》。
