Ghodbane R., Asmar S., Betzner M., Linet M., Pierquin J., Raoult Didier, Drancourt M. (2015). Rapid diagnosis of tuberculosis by real-time high-resolution imaging of Mycobacterium tuberculosis colonies. Journal of Clinical Microbiology, 53 (8), p. 2693-2696. ISSN 0095-1137.
Titre du document
Rapid diagnosis of tuberculosis by real-time high-resolution imaging of Mycobacterium tuberculosis colonies
Ghodbane R., Asmar S., Betzner M., Linet M., Pierquin J., Raoult Didier, Drancourt M.
Source
Journal of Clinical Microbiology, 2015,
53 (8), p. 2693-2696 ISSN 0095-1137
Culture remains the cornerstone of diagnosis for pulmonary tuberculosis, but the fastidiousness of Mycobacterium tuberculosis may delay culture-based diagnosis for weeks. We evaluated the performance of real-time high-resolution imaging for the rapid detection of M. tuberculosis colonies growing on a solid medium. A total of 50 clinical specimens, including 42 sputum specimens, 4 stool specimens, 2 bronchoalveolar lavage fluid specimens, and 2 bronchial aspirate fluid specimens were prospectively inoculated into (i) a commercially available Middlebrook broth and evaluated for mycobacterial growth indirectly detected by measuring oxygen consumption (standard protocol) and (ii) a home-made solid medium incubated in an incubator featuring real-time high-resolution imaging of colonies (real-time protocol). Isolates were identified by Ziehl-Neelsen staining and matrix-assisted laser desorption ionization-time of flight mass spectrometry. Use of the standard protocol yielded 14/50 (28%) M. tuberculosis isolates, which is not significantly different from the 13/50 (26%) M. tuberculosis isolates found using the real-time protocol (P = 1.00 by Fisher's exact test), and the contamination rate of 1/50 (2%) was not significantly different from the contamination rate of 2/50 (4%) using the real-time protocol (P = 1.00). The real-time imaging protocol showed a 4.4-fold reduction in time to detection, 82 +/- 54 h versus 360 +/- 142 h (P<0.05). These preliminary data give the proof of concept that real-time high-resolution imaging of M. tuberculosis colonies is a new technology that shortens the time to growth detection and the laboratory diagnosis of pulmonary tuberculosis.
