Comparative Analysis of 2 Diagnostic Devices for Detection of <i>Mycobacterium tuberculosis</i> and Drug Resistance in Almaty, Kazakhstan, to Determine the Optimal Diagnostic for Local Needs

Background: and drug resistance is crucial to reduce tuberculosis (TB) burden and prevent development of drug resistance in high-burden drug-resistant TB regions. Methods: From December 2021 to July 2022, sputum samples from 1214 adult patients with presumptive TB in Almaty, Kazakhstan, were tested by BD MAX MDR-TB (Becton Dickinson), Cepheid Xpert MTB/RIF, and mycobacterial growth indicator tube (MGIT) liquid culture for detection of TB and drug resistance to rifampicin (RIF) and isoniazid (INH). Results: When compared with MGIT, BD MAX sensitivity and specificity for TB detection were 90% and 87%, and Xpert MTB/RIF results were 86% and 92%. For RIF resistance, BD MAX sensitivity and specificity were 91% and 95%, and Xpert MTB/RIF results were 94% and 92%. For INH resistance, BD MAX sensitivity and specificity were 98% and 97%. Whole genome sequencing was conducted for 24 samples with discordant RIF resistance results among the 3 devices to determine mutations related to resistance. When compared with a composite standard based on whole genome sequencing and MGIT, Xpert MTB/RIF had higher sensitivity and specificity for RIF resistance than BD MAX. Conclusions: Countries with high burden of drug-resistant TB should carry out national prevalence surveys to assess rates of multidrug-resistant TB and INH monoresistance. Those with higher rates should consider adopting BD MAX due to its ability to accurately diagnose RIF and INH resistance.