To Study the Genetic Diversity of the Circulating Mycobacterium Tuberculosis Complex (MTBC) Strains Isolated from Previously Treated Patients

Abstract

Background & Methods: The aim of the study is to study the genetic diversity of the circulating Mycobacterium tuberculosis complex (MTBC) strains isolated from previously treated patients. All strains of tuberculosis contain some subpopulation of bacilli that are resistant to anti-TB drugs. However, in resistant strains, the proportion of such bacilli is considerably higher than the sensitive strains.

Results: There were 2 isolates resistant to all the four first line antituberculosis drugs (INH, RIF, SM and EMB), 4 isolates were resistant to INH, RIF, and EMB while 18 isolates were resistant to SM, RIF and INH.

Conclusion: In order to understand the transmission and epidemiology of TB globally as well as locally, the use of molecular typing methods has become imperative not only for understanding genetic diversity and population structure of MTBC but also for carrying out supervision and monitoring of TB control programs and for understanding TB epidemic. Spoligotyping is a PCR-based method that amplifies the spacer; the presence and absence of spacers will result in different polymorphisms. A total of 100 patients with sputum smear positive pulmonary tuberculosis from whom MTBC was grown in pure culture were included in this study. Among the 100 patients with TB, were sensitive to all four drugs while drug resistant isolates.