biostudies-literatureRigouts LUniversity of AntwerpEuropean Research CouncilDamien Foundation BelgiumDehousseEuropean Research Council Starting314-23https://www.ebi.ac.uk/biostudies/studies/S-EPMC4710215biostudies-literatureUnknown71(2)<h4>Objectives</h4>Mutations in the gyrase genes cause fluoroquinolone resistance in Mycobacterium tuberculosis. However, the predictive value of these markers for clinical outcomes in patients with MDR-TB is unknown to date. The objective of this study was to determine molecular markers and breakpoints predicting second-line treatment outcomes in M. tuberculosis patients treated with fourth-generation fluoroquinolones.<h4>Methods</h4>We analysed treatment outcome data in relation to the gyrA and gyrB sequences and MICs of ofloxacin, gatifloxacin and moxifloxacin for pretreatment M. tuberculosis isolates from 181 MDR-TB patients in Bangladesh whose isolates were susceptible to injectable drugs.<h4>Results</h4>The gyrA 90Val, 94Gly and 94Ala mutations were most frequent, with the highest reThe Journal of antimicrobial chemotherapySpecific gyrA gene mutations predict poor treatment outcome in MDR-TB.PMC4710215311725Hossain MAFissette KRieder HLCoeck NRigouts LVan Deun AAung KJde Rijk WBMeehan CJGumusboga Mde Jong BCfalseSpecific gyrA gene mutations predict poor treatment outcome in MDR-TB.<h4>Objectives</h4>Mutations in the gyrase genes cause fluoroquinolone resistance in Mycobacterium tuberculosis. However, the predictive value of these markers for clinical outcomes in patients with MDR-TB is unknown to date. The objective of this study was to determine molecular markers and breakpoints predicting second-line treatment outcomes in M. tuberculosis patients treated with fourth-generation fluoroquinolones.<h4>Methods</h4>We analysed treatment outcome data in relation to the gyrA and gyrB sequences and MICs of ofloxacin, gatifloxacin and moxifloxacin for pretreatment M. tuberculosis isolates from 181 MDR-TB patients in Bangladesh whose isolates were susceptible to injectable drugs.<h4>Results</h4>The gyrA 90Val, 94Gly and 94Ala mutations were most frequent, with the highest re2016-01-01T00:00:00Z2016 Feb2025-04-19T01:55:15.486Z2019-03-27T02:06:45ZS-EPMC47102152660424310.1093/jac/dkv360