Trial for drug susceptibility testing of Mycobacterium tuberculosis with live and dead cell differentiation

Sung Weon Ryu, Hyun Ho Kim, Mun Nam Bang, Young Kil Park, Sue Nie Park, Young Soo Shim, Seongman Kang, Gill Han Bai

Research output: Contribution to journalArticlepeer-review


Background: The resurgence of tuberculosis and outbreaks of multidrug resistant (MDR) tuberculosis have increased the emphasis for the development of new susceptibility testing of the Mycobacterium tuberculosis for the effective treatment and control of the disease. Conventional drug susceptibility testings, such as those using egg-based or agar-based media have some limits, such as the time required and difficulties in determining critical inhibitory concentrations, but these are still being used in many diagnostic laboratories because of no better alternatives, considering cost and accuracy. To overcome these limits, a rapid and simple method for new susceptibility testing, using live and dead assays, was applied for a bacterial cell viability assay to distinguish dead from live bacterial cells based on two-color fluorescence. Materials and Methods Strains: Forty strains were used in this study, 20 susceptible to all antituberculosis drugs and the other 20 resistant to the four first line antituberculosis drugs isoniazid, rifampicin, streptomycin and ethambutol. Antibiotics: The four antibiotics were dissolved in 7H9 broth to make the following solutions: 0.1μg isoniazid(INH)/ml, 0.4μg rifampicin(RMP)/mg, 4.0μg streptomycin(SM)/ml and 4.0μg ethambutol(EMB)/ml. Results: Live and dead Mycobacterium tuberculosis cells fluoresced green and red with the acridin (Syto 9) and propidium treatments, respectively, These results are very well accorded with conventional drug susceptibility testing by proportional method on Lowensen-Jensen media (L-J) containing 4 drugs (INH, RMP, EMB and SM), showing a 93.7% accordance rate in susceptible strains and 95% in resistant strains. Conclusion: The results of the drug susceptibility testing using the live and dead bacterial cell assay showed high accordance rates compared with the conventional proportion method on L-J. This finding suggests that the live and dead bacterial cell assay can be used as an alternative to conventional drug susceptibility testing for M. tuberculosis strains.

Original languageEnglish
Pages (from-to)261-267
Number of pages7
JournalTuberculosis and Respiratory Diseases
Issue number3
Publication statusPublished - 2004 Mar


  • Live and dead cell
  • Susceptibility testing
  • Tuberculosis

ASJC Scopus subject areas

  • Pulmonary and Respiratory Medicine
  • Infectious Diseases


Dive into the research topics of 'Trial for drug susceptibility testing of Mycobacterium tuberculosis with live and dead cell differentiation'. Together they form a unique fingerprint.

Cite this