<sup>*</sup>Department of Medicine, University of Saskatchewan, Saskatoon, Saskatchewan.
<sup>†</sup>Department of Community Health Sciences, University of Calgary, Calgary.
Int J Tuberc Lung Dis. 2015 Mar;19(3):278-84, i-iii. doi: 10.5588/ijtld.14.0262.
Xpert(®) MTB/RIF is a commercially available nucleic acid amplification test developed for the diagnosis of pulmonary tuberculosis (PTB).
To determine the diagnostic accuracy of Xpert for the detection of extra-pulmonary tuberculosis (EPTB).
We searched MEDLINE, EMBASE and Global Health databases from January 2010 to 15 August 2014 for studies of diagnostic performance in which Xpert was examined against culture for patients with clinically suspected EPTB. Bivariate random effects models were used to provide pooled estimates of diagnostic accuracy.
Thirty-six studies were identified, with a pooled sensitivity and specificity of respectively 77% (95%CI 66-85) and 97% (95%CI 94-98). Substantial variations existed between study estimates of sensitivity (I(2) = 99%) and specificity (I(2) = 96%). Among site-specific estimates for lymph, pleural fluid, cerebrospinal fluid, gastro-intestinal and urinary samples, the pooled sensitivity was lower in pleural fluid (37%, 95%CI 26-50, meta-regression P < 0.001) and higher in lymph node samples (87%, 95%CI 75-95, meta-regression P = 0.03).
Xpert has high specificity but limited sensitivity for the detection of EPTB. Although positive Xpert test results may be useful in rapidly identifying EPTB cases, negative test results provide less certainty for ruling out disease.
Xpert(®) MTB/RIF 是一种商业化的核酸扩增检测方法，用于诊断肺结核（PTB）。
确定 Xpert 检测肺外结核（EPTB）的诊断准确性。
我们检索了 MEDLINE、EMBASE 和 Global Health 数据库，以获取 2010 年 1 月至 2014 年 8 月 15 日期间关于 Xpert 与培养物对比诊断疑似 EPTB 患者的诊断性能的研究。使用双变量随机效应模型提供汇总诊断准确性的估计值。
共确定了 36 项研究，Xpert 的汇总敏感性和特异性分别为 77%（95%CI 66-85）和 97%（95%CI 94-98）。研究估计的敏感性（I² = 99%）和特异性（I² = 96%）之间存在很大差异。在针对淋巴、胸腔积液、脑脊液、胃肠和尿液样本的特定部位估计中，胸腔积液的汇总敏感性较低（37%，95%CI 26-50，meta 回归 P < 0.001），淋巴结样本的敏感性较高（87%，95%CI 75-95，meta 回归 P = 0.03）。
Xpert 检测 EPTB 的特异性高，但敏感性有限。虽然 Xpert 阳性检测结果可能有助于快速识别 EPTB 病例，但阴性检测结果对排除疾病的确定性较低。
