Current Microbiology

, Volume 24, Issue 3, pp 171–177 | Cite as

Amphotericin B synergy testing by the FCST

  • R. Scott Pore


The flow cytofluorometric susceptibility test (FCST) was incorporated into two in vitro synergy assays of amphotericin B-drug combinations. The FCST checkerboard assay and the FCST concentration-effect assay were developed to detect subtle modulation of amphotericin B fungicidal effects onCandida albicans andCryptococcus neoformans. Amphotericin B × cyclosporine A was a synergistic fungicidal combination against bothC. albicans andC. neoformans. Amphotericin B×gentamicin and amphotericin B×ketoconazole were synergistic combinations againstC. neoformans. In all cases tested, the synergy was effective when 0.50–0.62 μg amphotericin B/ml was used with>-0.50 μg of the other drug/ml. The fungicidal effect of ≥1.00 μg amphotericin B/ml overwhelmed the synergistic effects. A number of other drug combinations were additive, autonomous, or antagonistic.


Cyclosporine Synergistic Effect Gentamicin Amphotericin Ketoconazole 
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Copyright information

© Springer-Verlag New York Inc 1992

Authors and Affiliations

  • R. Scott Pore
    • 1
  1. 1.Department of Microbiology and ImmunologyWest Virginia University School of MedicineMorgantownUSA

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