Characterization of multiple and extensively drug resistant Mycobacterium tuberculosis isolates with different ofloxacin-resistance levels.

The goal of the study was to determine different mutation types in gyrA and gyrB genes in Mycobacterium tuberculosis strains with low-level (2 μg/ml) and high-level (10 μg/ml) ofloxacin (OFL) resistance and to compare genetic diversity of ofloxacin-resistant and susceptible M. tuberculosis isolates. M.