Mutations Associated with Pyrazinamide Resistance in the Clinical Isolates of Mycobacterium tuberculosis
Pyrazinamide is one of the four first line drugs for treatment of tuberculosis. It has been widely accepted, that pyrazinamide (PZA) resistance in Mycobacterium tuberculosis is correlated with mutations in the pncA gene. In the present study, pyrazinamide susceptibility was tested in 65 clinical isolates of Mycobacterium tuberculosis by pncA gene sequencing and was then correlated with pyrazinamidase activity. 68% of the resistant isolates showed mutation in the pncA gene which was further correlated with an assay for pyrazinamidase activity.