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Comparative Study
. 2011 May;91(3):257-9.
doi: 10.1016/j.tube.2011.01.004. Epub 2011 Feb 25.

Time to detection of Mycobacterium tuberculosis as an alternative to quantitative cultures

C M Bark  1 , A Okwera, M L Joloba, B A Thiel, J G Nakibali, S M Debanne, W H Boom, K D Eisenach, J L Johnson
Affiliations
Comparative Study

Time to detection of Mycobacterium tuberculosis as an alternative to quantitative cultures

C M Bark et al. Tuberculosis (Edinb). 2011 May.

Abstract

Testing new drugs is critical to improving the treatment of tuberculosis. Quantitative cultures of Mycobacterium tuberculosis on solid media have been used in Phase 1 and 2 trials, but are time and resource intensive. Time to detection (TTD) of growth of M. tuberculosis in automated liquid culture systems is an alternative. TTD has been shown to correlate with CFU in quantitative cultures, and is faster and simpler to perform. We compared TTD in the BACTEC 460 liquid culture system with CFU in a clinical trial that included 110 subjects. Comparing all sputum cultures collected between baseline and 2 months we found a strong negative correlation between log(10) CFU and TTD (rho = -0.91). In addition, when TTD at baseline was compared with 1 and 2 month sputum culture positivity, subjects whose cultures were negative after 1 and 2 months had a significantly longer median baseline TTD compared with subjects whose cultures were positive at 1 and 2 months (5 vs. 3 days and 3 vs. 2 days, respectively). TTD compares closely with CFU and represents a faster, simpler alternative to quantitative cultures.

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Figures

Figure
Figure
Paired sputum bacillary load (log10 cfu/ml) versus time to detection in 768 sputum samples from 107 patients collected on days 0, 2, 4, 7, 14, 28, 42, and 60 of anti-TB treatment.
See this image and copyright information in PMC

References

    1. Epstein MD, Schluger NW, Davidow AL, Bonk S, Rom WN, Hanna B. Time to detection of Mycobacterium tuberculosis in sputum culture correlates with outcome in patients receiving treatment for pulmonary tuberculosis. Chest. 1998;113:379–86. - PubMed
    1. Wallis RS, Patil S, Cheon SH, et al. Drug tolerance in Mycobacterium tuberculosis. Antimicrob Agents Chemother. 1999;43:2600–6. - PMC - PubMed
    1. Pheiffer C, Carroll NM, Beyers N, et al. Time to detection of Mycobacterium tuberculosis in BACTEC systems as a viable alternative to colony counting. Int J Tuberc Lung Dis. 2008;12:792–8. - PubMed
    1. Hesseling AC, Walzl G, Enarson DA, et al. Baseline sputum time to detection predicts month two culture conversion and relapse in non-HIV-infected patients. Int J Tuberc Lung Dis. 2010;14:560–70. - PubMed
    1. Diacon AH, Maritz JS, Venter A, et al. Time to detection of the growth of Mycobacterium tuberculosis in MGIT 960 for determining the early bactericidal activity of antituberculosis agents. Eur J Clin Microbiol Infect Dis. 2010;29:1561–5. - PubMed

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