Selective Detection of DNA from Viable Mycobacterium tuberculosis Complex Strains Using the EMA-PCR Method

In this study, the ability to discriminate viable from dead cells of Mycobacterium tuberculosis complex (MTC), using an ethidium monoazide (EMA) treatment-dependent viable bacteria selection PCR kit was examined. Detection of dead bacteria was possible for bacterial concentrations in the range 1.5 × 10⁷-3.0 × 10⁷ CFU/mL, which was equivalent to McFarland No. 0.05-0.10. There was a significant difference between the results for viable and dead bacteria, and the sensitivity and specificity of this method for culture-negative samples from patients were 83% and 100%, respectively. To the best of our knowledge, this is the first successful selective detection of DNA from viable cells of MTC by EMA-PCR, using the viable bacteria selection kit for PCR (gram-positive), an EMA treatment kit. We believe that application of this method could promote earlier discharge of patients undergoing tuberculosis treatment by discriminating dead from viable cells.