Mycobacterium tuberculosis Drug Resistance and Evaluation of the Current Situation

Abstract

Aim: We aimed to determine the antituberculosis drug susceptibility status in Mycobacterium tuberculosis complex isolates, considering that current drug resistance rates will be an important indicator of the prevalence of primary drug resistance in the future. Material and Methods: All cases whose culture sample was taken with clinical suspicion of tuberculosis at Samsun Training and Research Hospital in the period between January 2018 and December 2023 and who had a positive result in at least one of the Acid-fast stain (AFS) and culture methods were included in the study. Results: The average age of the patients was 54.5±18.5 (range: 17-93) and 398 (74.1%) were male. In the study, 77.3% of the samples were sputum and 15.8% were bronchoalveolar lavage. 474 (88.3%) of the isolates were M. tuberculosis complex. 49% of the samples were positive with the AFS method, 96.5% with Mycobacteria Growth Indicator Tube (MGIT), and 84.5% with Löwenstein-Jensen (LJ) medium. The resistance rates in the isolates were 10.6%, 2.8%, 1.1% and 7.0% for isoniazid, rifampicin, ethambutol and streptomycin, respectively. All isolates resistant to rifampicin were also resistant to isoniazid. The rate of multidrug-resistant isolates was found to be 2.8%. The single drug resistance rate was found to be 14.0%. It was determined that the resistance rates before the pandemic were significantly higher than during the pandemic period. Conclusion: The resistance rates to isoniazid and streptomycin in M. tuberculosis complex isolates were around 10% and that the general resistance rates to primary anti-tuberculosis drugs decreased significantly during the pandemic period.