Accuracy of Tongue Swab Testing Using Xpert MTB-RIF Ultra for Tuberculosis Diagnosis
Accuracy of Tongue Swab Testing Using Xpert MTB-RIF Ultra for Tuberculosis Diagnosis
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DOI：
10.1128/jcm.00421-22
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发表时间：
2022-06-27
影响因子：
9.4
通讯作者：
Cattamanchi, A.
中科院分区：
文献类型：
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作者：
Andama, A.;Whitman, G. R.;Cattamanchi, A.
舌背拭子作为肺结核患者检测结核分枝杆菌（MTB）的替代方法已显示出前景。一些最令人鼓舞的结果来自使用人工定量KR （qPCR）分析拭子的研究。使用自动造父变星Xpert MTB/RIF Ultra qPCR检测（Xpert Ultra）的研究显示，对舌拭子的灵敏度较低，可能是因为Xpert Ultra是针对痰而不是舌拭子样本进行优化的。使用两种在初步实验中表现出良好灵敏度的新型样品预处理方法，我们评估了Xpert Ultra对乌干达坎帕拉183名推定患有结核病的成年人采集的舌拭子的诊断准确性和半定量信号。相对于痰液Xpert Ultra参考标准，舌拭子Xpert Ultra的灵敏度为77.8%(95%可信区间[CI] 64.4 ~ 88.0)，特异性为100.0% （95% CI, 97.2 ~ 100.0）。与含痰Xpert Ultra和痰分枝杆菌培养的微生物参考标准（MRS）相比，敏感性为72.4% (95% CI, 59.1-83.3)，特异性保持不变。半定量的Xpert Ultra结果通常低于舌拭子比痰，周期阈值较高。使用舌拭子检测到的8种痰液中没有一种是“痕量”或“非常多”的。当无法收集痰液进行Xpert Ultra检测时，或在某些大规模筛查环境中，应考虑使用舌拭子。需要进一步优化舌拭子分析，以实现与基于痰液的结核病分子检测相同。
Tongue dorsum swabs have shown promise as alternatives to sputum for detecting Mycobacterium tuberculosis (MTB) in patients with pulmonary tuberculosis (TB). Some of the most encouraging results have come from studies that used manual quantitative KR (qPCR) to analyze swabs. Studies using the automated Cepheid Xpert MTB/RIF Ultra qPCR test (Xpert Ultra) have exhibited less sensitivity with tongue swabs, possibly because Xpert Ultra is optimized for testing sputum, not tongue swab samples. Using two new sample preprocessing methods that demonstrated good sensitivity in preliminary experiments, we assessed diagnostic accuracy and semi-quantitative signals of Xpert Ultra performed on tongue swabs collected from 183 adults with presumed TB in Kampala, Uganda. Relative to a sputum Xpert Ultra reference standard, the sensitivity of tongue swab Xpert Ultra was 77.8% (95% confidence interval [CI] 64.4-88.0) and specificity was 100.0% (95% CI, 97.2-100.0). When compared to a microbiological reference standard (MRS) incorporating both sputum Xpert Ultra and sputum mycobacterial culture, sensitivity was 72.4% (95% CI, 59.1-83.3) and specificity remained the same. Semi-quantitative Xpert Ultra results were generally lower with tongue swabs than with sputum, and cycle threshold values were higher. None of the eight sputum Xpert Ultra "trace" or "very loot results were detected using tongue swabs. Tongue swabs should be considered when sputum cannot be collected for Xpert Ultra testing, or in certain mass-screening settings. Further optimization of tongue swab analysis is needed to achieve parity with sputum-based molecular testing for TB.