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

Abstract

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.

Resistance Rates of Mycobacterium tuberculosis Complex Isolates to Primary Anti-tuberculosis Drugs: A 5-Year Retrospective Study

“…In our study, 65.6% of the samples detected positive by automated culture were found positive by EZN staining method. EZN staining positivity rate was which is in line with studies done by Behcet et al and Balcı et al (12,26). Although direct microscopy examination is broadly used in TB diagnosis, the sensitivity varies according to numerous factors such as the density of bacilli in the sample, decontamination procedures and the examiner experience.…”

“…Despite many studies in the literature have reported that tuberculosis is common among young people (22)(23)(24)(25), in our study the vast majority of TB cases were in the age group 56-75 years (42.2%), With aging, many elements can play a crucial role in acquiring TB such as suppressed immune system due to drugs or other conditions, higher tendency to respiratory diseases, and activation of latent TB infection. The most frequent clinical manifestation of TB infections was pulmonary TB 139 (90.3%) while extrapulmonary cases were only 15 (9.7%), in accordance with many previous literature (12,13,(25)(26)(27). Since the primary location of the bacteria is the lungs, extrapulmonary involvement is expected to be low.…”

“…The material obtained after the preliminary preparation was inoculated on BACTEC MGIT 960 TB automated system (Becton Dickinson, USA) and Löwenstein-Jensen (LJ) medium according to the recommendations of the manufacturer. The Ehrlich-Ziehl-Neelsen (EZN) staining method was used for acid-fast bacilli (AFB) detection in direct smear preparations (12). Cultures were left for incubation for up to 42 days (10).…”