Institute of Microbiology, University of Lausanne, University Hospital of Lausanne, Lausanne, Switzerland.
Pneumology Service, University Hospital of Lausanne, Lausanne, Switzerland.
Clin Microbiol Infect. 2019 Nov;25(11):1370-1376. doi: 10.1016/j.cmi.2019.03.021. Epub 2019 Mar 28.
Tuberculosis diagnosis has dramatically improved since the introduction of the rapid molecular test Xpert MTB/RIF (Xpert) detecting M. tuberculosis and rifampicin resistance directly from clinical specimens, therefore shortening the turnaround time, reducing patient's isolation period and decreasing the time to start anti-TB drugs. The new version, Xpert MTB/RIF Ultra (Ultra), displays a higher sensitivity and an improved rifampicin resistance detection. Both tests have been endorsed by the World Health Organisation.
Xpert and Ultra rapidly became widespread and paved the way for new approaches and new paradigms as well as for the development of molecular point-of-care tests (POCTs). In this narrative review, we aimed to address their performance in the diagnosis of tuberculosis and to discuss the expectations of these tests as well as their limits and the unmet needs.
Peer-reviewed publications addressing the diagnostic performance of Ultra and Xpert.
We focused on publications that evaluated the performance of Ultra and Xpert on the same group of patients or the same set of specimens in different tuberculosis-burden settings.
The studies published so far reported an increased sensitivity of Ultra when compared to Xpert, which represents a benefit for tuberculosis diagnosis. The fact that such a sensitive assay cannot distinguish between alive and dead bacilli emphasizes that caution should be exercised regarding indications and interpretation of results. Additional studies are needed to determine the true performance for the diagnosis of extrapulmonary tuberculosis because of the great diversity of the specimens.
自从快速分子检测 Xpert MTB/RIF（Xpert）问世以来，结核病的诊断有了显著的改善，它可以直接从临床标本中检测结核分枝杆菌和利福平耐药性，从而缩短了周转时间，减少了患者的隔离期，并加快了抗结核药物的使用。新版本 Xpert MTB/RIF Ultra（Ultra）显示出更高的灵敏度和改进的利福平耐药性检测。这两种检测方法都得到了世界卫生组织的认可。
Xpert 和 Ultra 迅速普及，为新方法和新范式的出现以及分子即时检测（POCT）的发展铺平了道路。在这篇叙述性综述中，我们旨在评估它们在结核病诊断中的性能，并讨论这些检测的预期、局限性以及未满足的需求。
涉及 Ultra 和 Xpert 诊断性能的同行评议出版物。
我们专注于那些评估 Ultra 和 Xpert 在不同结核病负担环境下对相同患者组或相同标本进行检测的性能的出版物。
迄今为止发表的研究报告显示，Ultra 与 Xpert 相比具有更高的灵敏度，这对结核病诊断有好处。但需要注意的是，这种高灵敏度的检测方法不能区分活细菌和死细菌，因此在适应证和结果解释方面应保持谨慎。需要进一步研究来确定其对肺外结核病诊断的真正性能，因为标本的多样性很大。
