Development and evaluation of a line probe assay for rapid identification of pncA mutations in pyrazinamide-resistant mycobacterium tuberculosis strains.

Resistance of Mycobacterium tuberculosis to pyrazinamide (PZA) derives mainly from mutations in the pnc,4 gene. We developed a reverse hybridization-based line probe assay with oligonucleotide probes designed to detect mutations in pnc,4. The detection of PZA resistance was evaluated in 258 clinical isolates of M. tuberculosis. The sensitivity and specificity of PZA resistance obtained by this new assay were both 100%, consistent with the results of conventional PZA susceptibility testing. This assay can be used with sputa from tuberculosis patients. It appears to be reliable and widely applicable and, given its simplicity and rapid performance, will be a valuable tool for diagnostic use.