ABSTRACT
Tuberculosis is a major public health problem throughout the world. TB's worldwide patterns of prevalence coupled with the increase in incidence of HIV infection threaten the health and lives of humans worldwide. Rapid detection of TB and the rapidly initiation of the administration of medication are important strategies for stopping the transmission of this disease transmission and its resistance to anti-TB drugs. Molecular methods are advantageous relative to conventional techniques due to their greater speed and sensitivity in the detection of TB. In this study, we targeted the cyp141 gene for the detection of Mycobacterium tuberculosis from clinical specimens [n = 123] by PCR and compared the sensitivity and specificity of this new target with those of IS6110 gene. Targeting of the cyp141 gene is more sensitive [97.1% for cultured isolates and 85.7% for direct specimens] than the targeting of the commonly used IS6110 gene [95.1% for cultured isolates and 42.9% for direct specimens], and the specificities of these two target genes were equal [100%]. The cyp141 gene can be used as a new target for the direct detection of Mycobacterium tuberculosis that seems to be superior to IS6110
ABSTRACT
Objective: To design a rapid test to detect the rifampin (RIF) and isoniazid (INH) resistant mutant based on polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) technique that analyzes the katG, rpoB genes.Methods:tuberculosis. To determine the susceptibility of isolates to anti TB drugs, the proportional method was used. Mutations presented within the amplified products of the katG, rpoB genes were evaluated by SSCP.Results:Using proportional method, 12 (11.6%) and 9 (8.7%) isolates were resistant respectively Biochemical test as well as IS6110 targeting PCR revealed 103 clinical samples were to INH and RIF and 9 (8.7%) isolates showed resistance to both drug (multi-drug resistant tuberculosis). Three (2.9%) multi-drug resistant tuberculosis and two INH resistant isolates were detected by the PCR-SSCP and sequencing. The sensitivity and specificity of PCR-SSCP for multi-drug resistant isolates were 33% and 100%, respectively.Conclusions:Complete agreement between SSCP and sequencing can indicate that resistance-associated mutations have occurred in other genes except our considered genes.