title: Rapid susceptibility testing for slowly growing nontuberculous mycobacteria using a colorimetric microbial viability assay based on the reduction of water-soluble tetrazolium WST-1.
abstract: Rapid susceptibility testing for slowly growing nontuberculous mycobacteria (NTM) using a colorimetric microbial viability assay based on the reduction of the water-soluble tetrazolium salt {2-(4-iodophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium, monosodium salt (WST-1)} using 2,3,5,6-tetramethyl-1,4-benzoquinone as an electron mediator was developed. Using the Clinical and Laboratory Standards Institute (CLSI) method, a long-term incubation time (7-14 days) was required to determine the minimum inhibitory concentrations (MICs) of the slowly growing NTM. The MICs for a variety of different antibiotics against the slowly growing NTM were determined by the WST-1 colorimetric method and compared with those obtained using the broth microdilution methods approved by the CLSI. Good agreement was found between the MICs determined after 3-4 days using the WST-1 colorimetric method and those obtained after 10-14 days using the broth microdilution method. The results suggest that the WST-1 colorimetric assay is a useful method for the rapid determination of the MICs for the slowly growing NTM.
authors.affiliation: Biotechnology and Food Research Institute, Fukuoka Industrial Technology Center, 1465-5 Aikawa-machi, Kurume, 839-0861, Japan. tukatani@fitc.pref.fukuoka.jp.
authors.forename: T
authors.initials: T
authors.lastname: Tsukatani
authors.affiliation: Biotechnology and Food Research Institute, Fukuoka Industrial Technology Center, 1465-5 Aikawa-machi, Kurume, 839-0861, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Suenaga
authors.affiliation: Dojindo Laboratories, Kumamoto, 861-2202, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Shiga
authors.affiliation: Dojindo Laboratories, Kumamoto, 861-2202, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Ikegami
authors.affiliation: Dojindo Laboratories, Kumamoto, 861-2202, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Ishiyama
authors.affiliation: Dojindo Laboratories, Kumamoto, 861-2202, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Ezoe
authors.affiliation: Laboratory of Food Bioscience, Department of Applied Microbial Technology, Faculty of Biotechnology and Life Science, Sojo University, Kumamoto, 860-0082, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Matsumoto
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology* / Q000627:therapeutic use*; D049109:Cell Proliferation / Q000187:drug effects*; D008826:Microbial Sensitivity Tests; D050296:Microbial Viability / Q000187:drug effects*; D009165:Mycobacterium Infections, Nontuberculous / Q000188:drug therapy*; D009170:Nontuberculous Mycobacteria / Q000187:drug effects* / Q000254:growth & development*; D013778:Tetrazolium Salts / Q000378:metabolism; D013997:Time Factors
chemical_list: C110656:2-(4-iodophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium; D000900:Anti-Bacterial Agents; D013778:Tetrazolium Salts