[Establishment and evaluation of nitrate reductase combined with mycobacteriophage assay].

OBJECTIVE: To establish a rapid, inexpensive, and simple drug susceptibility test (DST) for Mycobacterium tuberculosis (M. tb) and evaluate its feasibility. METHOD: We used nitrate reductase combined with mycobacteriophage assay (PhaB-NRA) to test 49 clinical M. tb isolates of, and the results were compared with those of PhaB-NRA and traditional absolute concentration method. RESULTS: The sensitivity, specificity, and accuracy of PhaB-NRA for rifampicin were 89.1%, 91.67%, and 89.8%; on the contrary, those of isonicotinyl hydrazide were 86.21%, 90.0%, and 87.8%, respectively. The coincidence between PhaB-NRA and traditional assay were 0.746 for rifampicin and 0.750 for isonicotinyl hydrazide. CONCLUSIONS: PhaB-NRA is an inexpensive, rapid, and simple DST method. It is a promising rapid screening technique for DST of M. tb.