Investigation of the Sensitivity of Mycobacterium Tuberculosis Strains Isolated from Various Clinical Samples in Eastern Turkey to Major Anti-tuberculosis Drugs

Objective: In the study, 419 Mycobacterium tuberculosis complex strains (MTC), which were isolated from samples sent to the Regional Tuberculosis Laboratory in our city between 2015 and 2019 with suspected tuberculosis from Erzurum and surrounding cities were investigated. Methods: Our research is a retrospective cross-sectional study and clinical samples sent to the Regional Public Health Laboratory with suspicion of Tuberculosis within a five-year period from January 2015 to December 2019 were first evaluated by using Ehrlich-Ziehl-Neelsen staining technique. The samples were then simultaneously inoculated into the automated culture system (BACTEC MGIT 960) with Löwenstein-Jensen medium. Sensitivity research was conducted for isoniazide, rifampicin, streptomycin and ethambutol antibiotics with BACTEC MGIT 960 system to samples defined by MTC identification test (TBc ID) from reproduction positive tubes. Results: In our study, 337 (80.4%) of the 419 MTC strains investigated in our study were susceptible to all major anti-TB drugs, while 82 (19.6%) were found to be resistant to at least one major anti-TB drug. The distribution of resistance ratios was isoniazid (11.9%), streptomycin (11.7%), rifampicin (4.1%), ethambutol (3.6%). Multi-drug resistant (MDR)–TB ratio (isoniazid+ rifampicin) was found to be (3.6%). Conclusions: In our study, in the strains in which resistance to anti-TB drugs was investigated, the highest drug resistance was determined for isoniazid. The lowest drug resistance was determined for ethambutol.