An analytic feasibility study of the BD MAXTM MDR-TB assay for testing of non-sputum specimens for detection of the Mycobacterium tuberculosis complex (MTBC) and isoniazid (INH) and rifampin (RIF) resistance

Rapid diagnosis of tuberculosis and drug resistance in extrapulmonary specimens can be challenging. The BD MAXTM multidrug resistant (MDR)-TB assay (BD MAXTM) has demonstrated high sensitivity and specificity for the detection of the Mycobacterium tuberculosis complex (MTBC) as well as resistance to INH and Rifampin (RIF) in pulmonary specimens but has not been rigorously assessed in extrapulmonary samples. We evaluated the diagnostic accuracy of the BD MAXTM assay for the detection of MTBC and drug resistance in extrapulmonary specimens spiked with MTBC from the Johns Hopkins strain collection. A total of 1083 tests were performed across multiple sample types, with an overall percent agreement of 94.8% (795/839) for detection of MTBC and 99% (379/383) and 96.4% (323/335) for determination of INH and RIF resistance-conferring mutations, respectively. The BD MAXTM assay provides same day detection of MTBC and drug-resistance results and could be a beneficial diagnostic test in extrapulmonary sample types. (c) 2023 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/)