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PubMed · 7956018

Multicenter comparison of a colorimetric microdilution broth method with the reference macrodilution method for in vitro susceptibility testing of yeast isolates.

M A Pfaller·B Buschelman·M J Bale·M Lancaster·A Espinel-Ingroff·J H Rex·M G Rinaldi
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Abstract

This multicenter study was performed to compare a colorimetric microdilution method with the NCCLS M27-P reference macrodilution method for the testing of yeast isolates against amphotericin B, fluconazole, and 5-fluorocytosine (5FC). Testing was performed on ten yeast isolates in five independent laboratories. All sites tested each isolate a total of 20 times with both methods. MICs were read after 48 h incubation. The macrodilution MIC reference range was defined as the modal MIC +/- 1-log2 dilution for each organism-antifungal agent combination. Agreement between the M27-P reference range results and the microdilution MICs was 86% with amphotericin B, 90% with fluconazole, and 93% with 5FC. Based on these data, it is apparent that new approaches, such as the colorimetric microdilution method, will provide MIC values comparable to the M27-P macrodilution method in a format that is more practical for use in a busy clinical laboratory.

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Amphotericin BAntifungal AgentsColony Count, MicrobialColorimetryFluconazoleFlucytosineHumansMicrobial Sensitivity TestsReference StandardsReference ValuesYeastsComparative StudyJournal ArticleMulticenter StudyResearch Support, Non-U.S. Gov't

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M A Pfaller, B Buschelman, M J Bale, M Lancaster, A Espinel-Ingroff, J H Rex, M G Rinaldi. 1994. Multicenter comparison of a colorimetric microdilution broth method with the reference macrodilution method for in vitro susceptibility testing of yeast isolates.. https://doi.org/10.1016/0732-8893(94)90044-2

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Amphotericin B↗
PubMed2007

Correlation of Neo-Sensitabs tablet diffusion assay results on three different agar media with CLSI broth microdilution M27-A2 and disk diffusion M44-A results for testing susceptibilities of Candida spp. and Cryptococcus neoformans to amphotericin B, caspofungin, fluconazole, itraconazole, and voriconazole.

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Amphotericin B↗