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An evaluation of the Xpert MTB/RIF assay and detection of false-positive rifampicin resistance in Mycobacterium tuberculosis,☆☆

https://doi.org/10.1016/j.diagmicrobio.2012.06.013Get rights and content

Abstract

Recent reports suggest that false-positive rifampicin resistance may be assigned by the Xpert MTB/RIF assay. We analysed 169 specimens using the MTB/RIF assay. Using culture as the gold standard, we found that the assay had 100% sensitivity and specificity for detecting M. tuberculosis. However, we found that the assay incorrectly assigned rifampicin resistance in 4/13 (31%) of cases.

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Acknowledgment

The authors would like to thank Dr Ivan Bastian for kindly reviewing the manuscript.

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Funding: This study was supported by internal funding.

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Conflicts of interests: None for all authors.

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