Table 1.
Synergy between FLU and FAR (200 μM) of C. auris isolates determined according to MIC50 values.
| Strain | MIC50 FLU (Alone) (μg/mL) | Interpretation | MIC50 FAR (Alone) (μM) | MIC50 FLU with 200 μM FAR (μg/mL) | FIC Index | Interpretation |
|---|---|---|---|---|---|---|
| C. auris H261 | 0.125 | Susceptible | 500 | 0.125 | 1.4 | Indifferent |
| C. auris S | 16 | Susceptible * | 400 | 4 | 0.75 | Partial synergy |
| C. auris R | 256 | Resistant | 500 | 1 | 0.4 | Synergy |
FLU—Fluconazole; FAR—Farnesol; MIC50—Minimal inhibitory concentration of tested antifungals inhibiting the growth of yeast cells by 50% compared to the control sample without an agent. * Isolate C. auris S is susceptible according to the tentative breakpoint value for C. auris, which is 32 μg/mL (https://www.cdc.gov/fungal/candida-auris/c-auris-antifungal.html, accessed on 29 May 2020). However, MIC50 of 16 μg/mL is considered to be relatively high and means significantly decreased susceptibility of this isolate to FLU.