Evaluation of the resistance patterns of Mycobacterium tuberculosis complex strains to antituberculous drugs

Aim: To determine the resistance profile of Mycobacterium tuberculosis complex (MTBC) strains to first-line antituberculous drugs. Methods: A total of 138 patients with MTBC growth from 2008-2018 were evaluated retrospectively. The Ehrlich-Ziehl-Neelsen (EZN) staining method was used for direct smear preparations, the BACTEC MGIT 460 TB system the Lowenstein-Jensen medium for culture planting and the BACTEC NAP test for the diagnosis of MTBC. Susceptibility tests were performed using the BACTEC MGIT 460 TB system with the streptomycin, isoniazid, rifampicin and ethambutol (SIRE) kit in accordance with the manufacturer's recommendations. Results: Of the total 138 tuberculosis (TB) cases, 44 (31.9%) were female and 94 (68.1%) were male. MTBC was most frequently isolated from pulmonary specimens (90.6%). Acid-resistant bacilli (ARB) positivity was detected in 88 (63.8%) samples by EZN staining for culture-positive samples. In our study, without considering single or multiple drug resistance (MDR), total resistance rates in MTBC strains were determined for, isoniazid (INH), rifampicin (RIF), ethambutol (EMB), and streptomycin (SM); 10.1%, 4.3%, 2.9%, and 12.3% respectively. While the susceptibility to all drugs was 82.6%, multiple drug–resistant tuberculosis (MDR-TB) was 2.9%. Conclusion: These results are important since they are the first data reported from our province regarding the determination of the resistance profile to anti-TB drugs. Resistance rates in our study were very close to the 2016 data average of the Ministry of Health of Turkey. Determination of TB resistance profiles, as well as proper and regular treatment, will contribute to the control of MDR-TB.