Bedaquiline delamanid, and linezolid minimum inhibitory concentration distributions and resistance-related gene mutations in multidrug-resistant tuberculosis strains isolated from south of Turkey

Delamanid, bedaquiline, and linezolid are three newer drugs that have been approved for the treatment of MDR and XDR tuberculosis (TB). The use of drug susceptibility testing is essential for correct diagnosis and treatment with these medications, and may entail quicker molecular approaches. The present study's objective is to evaluate the MICs and mutations in genes linked to resistance of MDR and completely drug-susceptible M. tuberculosis strains isolated from clinical samples of tuberculosis suspects given to THUM from the Cukurova Region of Turkey. The minimum inhibitory concentrations (MICs) of delamanid, bedaquiline, and linezolid were determined with the use of a semiautomated MGIT 960 system, EpiCenter software, and a TB eXiST module. The PCR results of 71 MTB isolates, , were sequenced and aligned with those of M. tuberculosis H37Rv.The MICs for bedaquiline, delamanid, and linezolid ranged from ≤0.025 to 6.4 mg/L, 0.005 to 0.32 mg/L, and 0.125 to 2 mg/L respectively. Multiple mutations were detected in both drug-sensitive and -resistant strains. We did not identify specific mutations involved with bedaquiline, delamanid, or linezolid resistance. However Further research is required to establish the genetic mechanisms behind these drugs' resistance.