Bone Infection Unit, Nuffield Orthopaedic Centre, Oxford University Hospitals , Oxford , United Kingdom.
Center for Musculoskeletal Infections, Department of Orthopaedic and Trauma Surgery, University Hospital Basel , Basel , Switzerland.
J Bone Joint Surg Am. 2021 Jun 2;103(11):977-983. doi: 10.2106/JBJS.20.00409.
The recent consensus definition for the diagnosis of fracture-related infection (FRI) includes the identification of indistinguishable microorganisms in at least 2 surgical deep-tissue specimens as a confirmatory criterion. However, this cut-off, and the total number of specimens from a patient with suspected FRI that should be sent for microbiological testing, have not been validated. We endeavored to estimate the accuracy of different numbers of specimens and diagnostic cut-offs for microbiological testing of deep-tissue specimens in patients undergoing surgical treatment for possible FRI.
A total of 513 surgical procedures in 385 patients with suspected FRI were included. A minimum of 2 surgical deep-tissue specimens were submitted for microbiological testing; 5 or more specimens were analyzed in 345 procedures (67%). FRI was defined by the presence of any confirmatory criteria other than microbiology. Resampling was utilized to model the sensitivity and specificity of diagnostic cut-offs for the number of surgical specimens yielding indistinguishable microorganisms and for the total number of specimens. The likelihood of detecting all clinically relevant microorganisms was also assessed.
A diagnostic cut-off of at least 2 of 5 specimens with indistinguishable microorganisms identified by culture was 68% sensitive (95% confidence interval [CI], 62% to 74%) and 87% specific (95% CI, 81% to 94%) for the diagnosis of FRI. Two out of 3 specimens were 60% sensitive (95% CI, 55% to 66%) and 92% specific (95% CI, 88% to 96%). Submitting only 3 deep-tissue specimens risked missing clinically relevant microorganisms in at least 1 in 10 cases.
The present study was the first to validate microbiological criteria for the diagnosis of FRI, supporting the current confirmatory diagnostic criteria for FRI. Analysis of at least 5 deep-tissue specimens in patients with possible FRI is recommended.
Diagnostic Level III. See Instructions for Authors for a complete description of levels of evidence.
最近的骨折相关感染（FRI）诊断共识定义包括在至少 2 个外科深部组织标本中鉴定出无法区分的微生物作为确认标准。然而，这个截止值以及疑似 FRI 患者应送检进行微生物检测的标本总数尚未得到验证。我们努力评估不同数量的标本和微生物检测的诊断截止值在接受手术治疗疑似 FRI 的患者中的准确性。
共纳入 385 例疑似 FRI 患者的 513 例手术。至少有 2 个外科深部组织标本进行了微生物检测；345 例（67%）分析了 5 个或更多标本。除了微生物学以外的任何确认标准都可定义为 FRI。利用重采样来模拟用于鉴定产生无法区分的微生物的外科标本数量和标本总数的诊断截止值的敏感性和特异性。还评估了检测所有临床相关微生物的可能性。
培养鉴定出至少 5 个标本中有 2 个无法区分的微生物的诊断截止值，对 FRI 的诊断具有 68%的敏感性（95%置信区间[CI]，62%至 74%）和 87%的特异性（95%CI，81%至 94%）。2 个标本中有 60%的敏感性（95%CI，55%至 66%）和 92%的特异性（95%CI，88%至 96%）。仅提交 3 个深部组织标本可能会导致在 10 例中至少有 1 例漏检临床相关的微生物。
本研究首次验证了 FRI 诊断的微生物学标准，支持目前 FRI 的确认性诊断标准。建议对疑似 FRI 的患者分析至少 5 个深部组织标本。
诊断 III 级。有关证据水平的完整描述，请参见作者说明。
