Abstract
A flow cytofluorometric susceptibility test (FCST) for in vitro antifungal drug testing ofCandida albicans was developed. Membrane damage was indicated by increased cellular fluorescence owing to propidium iodide or rose bengal uptake. Ketoconazole caused an exponential dose-response effect, best defined by Emax, at therapeutically achievable concentrations (0.02–0.2 µg/ml). This effect was not comparable to the conventional minimum inhibitory concentration (MIC) effect elicited by higher antibiotic concentrations. Amphotericin B, on the other hand, did not elicit Emax, but caused a >1 log dose-response effect which did correspond to the MIC. 5-Fluorocytosine susceptibility was also measurable. Other cytometric data indicating abnormal growth and growth inhibition, as well as conventional growth inhibition testing, confirmed that the 10-h FCST measured useful parameters of in vitro susceptibility.
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Pore, R.S. Antibiotic susceptibility testing ofCandida albicans by flow cytometry. Current Microbiology 20, 323–328 (1990). https://doi.org/10.1007/BF02091913
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DOI: https://doi.org/10.1007/BF02091913