Ann Lab Med.  2014 Jan;34(1):26-30. 10.3343/alm.2014.34.1.26.

Early Detection of Mycobacteria Using a Novel Hydrogel Culture Method

• Jang MH
• Kim SY
• Kim CK
• Hwang SH
• Park BK
• Kim SS
• Lee EY
• Chang CL

• KMID: 1781356
• DOI: http://doi.org/10.3343/alm.2014.34.1.26

Abstract

BACKGROUND
Early laboratory detection of Mycobacterium tuberculosis is crucial for controlling tuberculosis. We developed a hydrogel mycobacterial culture method that retains the advantages of both solid and liquid methods in terms of speed, cost, and efficiency.
METHODS
Mycobacterium bovis bacillus Calmette-Guerin (BCG) suspensions and 200 acid-fast bacilli (AFB)-positive clinical specimens were inoculated in Middlebrook 7H9 liquid media (Becton-Dickinson and Company, USA) and mixed with 75 microL of 9-fluorenylmethoxycarbonyl (Fmoc)-Phe-Phe-OH hydrogel stock solution in an Eppendorf tube just before culture incubation. The mixtures were cultured at 37degrees C for as long as 14 days to monitor culture status.
RESULTS
The number of M. bovis BCG increased with time. For 200 AFB smear-positive specimens, 155 of 158 conventional culture-positive specimens and 4 culture-negative or contaminated specimens yielded positive cultures within 14 days. For 128 specimens positive with the liquid culture method, the time to positive culture using the hydrogel method (mean, 12.6 days; range, 7 to 14 days) was significantly shorter than that for conventional liquid culture (mean, 16.2 days; range, 6 to 31 days; P<0.0001).
CONCLUSIONS
The hydrogel scaffold culture system is useful for timely, economical, and efficient detection of mycobacteria in clinical specimens.

Keyword

Hydrogel scaffold; Mycobacterium tuberculosis; Mycobacterial culture

MeSH Terms

Bacteriological Techniques/*methods
Culture Media/chemistry
Early Diagnosis
Humans
Hydrogel/*chemistry
Mycobacterium tuberculosis/*isolation & purification
Tuberculosis/diagnosis/*microbiology
Culture Media
Hydrogel

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