The US Food and Drug Administration (FDA) has added a new tool to clinicians’ tuberculosis (TB) armamentarium. The agency approved the Xpert MTB/RIF assay to detect DNA of the Mycobacterium tuberculosis complex in sputum samples, as well as genetic mutations that confer resistance to the first-line TB drug rifampin.
The assay is a nucleic acid amplification-based (NAA) test with sensitivity and specificity considered comparable with other FDA-approved NAA assays used to detect M tuberculosis complex. In a multicenter study of patients suspected of having TB, the new assay’s sensitivity was 95% and specificity was 99% in detecting rifampin resistance.
New Assay Detects TB Bacteria and Resistance to Rifampin. JAMA. 2013;310(23):2498. doi:10.1001/jama.2013.283912