Molecular Diagnosis of drug-resistant Mycobacterium Tuberculosis Isolates by IS6110 gene in patients suspected to Tuberculosis in Tehran City

Introduction: Mycobacterium tuberculosis is one of the most dangerous infectious diseases in the world. Determining the diagnosis of M. tuberculosis based on culture and phenotypic tests takes weeks and do not have appropriate methods to evaluate a definitive diagnosis. Therefore, the PCR technique of the IS6110 gene is an accurate, quick, and inexpensive method for the detection of M. tuberculosis. Generally, the purpose of the study is to provide molecular identity strains of M. tuberculosis resistant to first-line drugs (rifampin and isoniazid) detected from patients by PCR-IS6110. Materials and Methods: Of the 3012 Mycobacterium suspected cases, 60 samples of mycobacterium drug-resistant (MDR) were examined by smear, culture, phenotypic tests, and antibiogram. The isolates were identified by IS6110 gene after DNA extraction. Results & Conclusions: Out of 60 collected samples, 54 positive samples from the M. tuberculosis group (90%) and 6 negative samples (10%) from non-tuberculosis group were reported. Out of 3012 clinical samples, 100 samples cultures were positive (3.3%), Out of 54 M. tuberculosis were samples, 3 samples were resistant to rifampin (5%) and the other samples were MDR (94%). The IS6110 gene is one of the best marker genes for the Mycobacterium complex differentiation. This study showed that PCR-IS6110 technique is a simple and accurate method for identifying drug resistance of clinical isolates of M. tuberculosis in clinical Laboratories. Instead of using phenotypic methods which is time-consuming and have variable results in diagnostic laboratories, it is suggested to use molecular methods directly, especially IS6110 gene sequencing.

Molecular Diagnosis of drug-resistant Mycobacterium Tuberculosis Isolates by IS6110 gene in patients suspected to Tuberculosis in Tehran City Keywords:

Molecular detection , Mycobacterium tuberculosis , MDR strains , Molecular detection , IS6110 gene