Inter- and intra-assay reproducibility of microplate alamar blue assay results for isoniazid, rifampicin, ethambutol, streptomycin, ciprofloxacin, and capreomycin drug susceptibility testing of Mycobacterium tuberculosis

Brian Leonard, Jorge Coronel, Mark Siedner, Louis Grandjean, Luz Caviedes, Pilar Navarro, Robert H Gilman, David A J Moore

Research output: Contribution to journalArticle


The intersample and intrasample variability of the results obtained with the microplate Alamar blue assay for the indirect drug susceptibility testing of Mycobacterium tuberculosis was investigated. Between 1.2 and 8.5% of paired MICs differed by more than one twofold dilution, resulting in discordant susceptible-resistant designations at frequencies between 0.6% (rifampin) and 18.9% (ethambutol).

Original languageEnglish (US)
Pages (from-to)3526-3529
Number of pages4
JournalJournal of Clinical Microbiology
Issue number10
Publication statusPublished - Oct 2008


ASJC Scopus subject areas

  • Microbiology (medical)

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