TY - JOUR
T1 - Determination of antifungal drug susceptibilities of Aspergillus species by a fluorenscence-based microplate assay
AU - Arunmozhi Balajee, S.
AU - Imhof, Alexander
AU - Gribskov, Jennifer L.
AU - Marr, Kieren A.
N1 - Funding Information:
This work was supported by National Institutes of Health grant R21 AI55928 to K.A.M.
PY - 2005/1
Y1 - 2005/1
N2 - Objectives: We have investigated the use of a viability dye, chloromethylfluorescein di-acetate (CMFDA), for antifungal susceptibility testing in a fluorescence microplate (FM) assay format. Methods: For this FM assay, conidia were incubated in increasing concentrations of antifungal drug for 16h and stained with CMFDA. Fluorescence, measured as mean fluorescence units (MFU) in a fluorescence microplate reader, was graphed relative to that of a drug-free control, and the MIC was defined as the lowest concentration of the drug that resulted in complete reduction (100%) in MFU for amphotericin B, or 90% reduction in MFU for itraconazole and voriconazole. Susceptibilities of 10 clinical isolates of Aspergillus fumigatus, Aspergillus terreus and Aspergillus niger to amphotericin B, itraconazole and voriconazole were tested in a blinded fashion using the FM and the NCCLS methods. Results and conclusions: Reproducibility of the FM assay was excellent, and results correlated with those of the NCCLS microdilution method. The FM assay appears to be a rapid, objective method for testing fungal susceptibilities to itraconazole, voriconazole and amphotericin B.
AB - Objectives: We have investigated the use of a viability dye, chloromethylfluorescein di-acetate (CMFDA), for antifungal susceptibility testing in a fluorescence microplate (FM) assay format. Methods: For this FM assay, conidia were incubated in increasing concentrations of antifungal drug for 16h and stained with CMFDA. Fluorescence, measured as mean fluorescence units (MFU) in a fluorescence microplate reader, was graphed relative to that of a drug-free control, and the MIC was defined as the lowest concentration of the drug that resulted in complete reduction (100%) in MFU for amphotericin B, or 90% reduction in MFU for itraconazole and voriconazole. Susceptibilities of 10 clinical isolates of Aspergillus fumigatus, Aspergillus terreus and Aspergillus niger to amphotericin B, itraconazole and voriconazole were tested in a blinded fashion using the FM and the NCCLS methods. Results and conclusions: Reproducibility of the FM assay was excellent, and results correlated with those of the NCCLS microdilution method. The FM assay appears to be a rapid, objective method for testing fungal susceptibilities to itraconazole, voriconazole and amphotericin B.
KW - Aspergillus spp.
KW - Fluorescent dyes
KW - MICS
KW - Susceptibility testing
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U2 - 10.1093/jac/dkh489
DO - 10.1093/jac/dkh489
M3 - Article
C2 - 15546970
AN - SCOPUS:13244274978
SN - 0305-7453
VL - 55
SP - 102
EP - 105
JO - Journal of Antimicrobial Chemotherapy
JF - Journal of Antimicrobial Chemotherapy
IS - 1
ER -