Molecular characterization of Mycobacterium tuberculosis isolates resistance to first and second line drug on gene effect in the Clinical samples from suspected patients to Tuberculosis

Diagnosis of drug-resistant tuberculosis is of high value considering the importance of controlling tuberculosis. Identifying and introducing a rapid and specific diagnostic method for the causative agent of tuberculosis, Mycobacterium tuberculosis, is of great importance. The aim of this study is molecular characterization the presence of drug-resistant Mycobacterium tuberculosis to first- and second-line drugs in suspected tuberculosis patients.

This study was conducted on 2895 patients referred to different laboratory centers who were suspected to tuberculosis. The samples that were positive on the culture medium were examined by the drug resistance evaluation method and also the sequencing was performed on drug resistant genes including katG, rpoB, rrsL and gyrA to identify the corresponding mutations.

During the study period from October 2018 to March 2022, 2895 people, a total of 283 positive samples and 60 resistant samples were isolated, and the relevant mutations in each gene were determined based on nucleotide changes on the relevant genes.

Due to the fact that the diagnosis of tuberculosis, especially in the case of Mycobacterium tuberculosis, is time consuming especially when samples are positive and it takes a long time to perform the resistance evaluation test. So molecular identification and identification of the relevant mutations on the related drug-resistance genes, provides the possibility of accurate diagnosis and timely treatment