TABLE 3.
In vitro susceptibilities of Candida species to four antifungal agents after 24 and 48 h of incubation
| Species (no. of isolates) | Antifungal agent | MIC (μg/ml) at the indicated timea:
|
% Resistant atb:
|
||||||
|---|---|---|---|---|---|---|---|---|---|
| Range
|
50%
|
90%
|
|||||||
| 24 h | 48 h | 24 h | 48 h | 24 h | 48 h | 24 h | 48 h | ||
| C. albicans (240) | Amphotericin B | 0.6–1 | 0.25–2 | 0.12 | 0.5 | 0.25 | 1 | 0 | 0 |
| Flucytosine | ≤0.06–4 | ≤0.06–>64 | ≤0.06 | 0.12 | 0.25 | 1 | 0 | 3 | |
| Itraconazole | ≤0.008–>8 | ≤0.008–>8 | 0.016 | 0.03 | 0.03 | >8 | 1 | 21 | |
| Fluconazole | ≤0.25–>256 | ≤0.25–>256 | ≤0.25 | 0.5 | ≤0.25 | 128 | 1 | 13 | |
| C. glabrata (67) | Amphotericin B | 0.12–1 | 0.5–4 | 0.25 | 1 | 1 | 4 | 0 | 7 |
| Flucytosine | ≤0.06–4 | ≤0.06–4 | ≤0.06 | ≤0.06 | ≤0.06 | 0.12 | 0 | 0 | |
| Itraconazole | 0.003–4 | 0.06–>8 | 0.25 | 1 | 1 | 4 | 13 | 58 | |
| Fluconazole | 1–>256 | 2–>256 | 4 | 8 | 64 | 64 | 9 | 13 | |
| C. parapsilosis (53) | Amphotericin B | 0.03–0.5 | 0.06–2 | 0.12 | 0.5 | 0.25 | 1 | 0 | 0 |
| Flucytosine | ≤0.06–0.12 | ≤0.06–1 | ≤0.06 | 0.12 | ≤0.06 | 0.25 | 0 | 0 | |
| Itraconazole | ≤0.008–0.25 | 0.016–0.5 | 0.03 | 25 | 0.12 | 0.25 | 0 | 0 | |
| Fluconazole | ≤0.25–1 | ≤0.25–4 | 0.5 | 1 | 1 | 2 | 0 | 0 | |
| C. tropicalis (41) | Amphotericin B | 0.06–1 | 0.25–2 | 0.25 | 1 | 0.5 | 1 | 0 | 0 |
| Flucytosine | ≤0.06–>64 | ≤0.06–>64 | ≤0.06 | 0.25 | 0.12 | 64 | 5 | 10 | |
| Itraconazole | ≤0.008–4 | ≤0.016–>8 | 0.06 | 0.25 | 0.5 | >8 | 5 | 32 | |
| Fluconazole | ≤0.25–16 | ≤0.25–>256 | 0.5 | 1 | 8 | >256 | 0 | 27 | |
| C. lusitaniae (15) | Amphotericin B | 0.12–1 | 0.5–4 | 0.5 | 1 | 1 | 4 | 0 | 13 |
| Flucytosine | ≤0.06 | ≤0.06 | ≤0.06 | ≤0.06 | ≤0.06 | ≤0.06 | 0 | 0 | |
| Itraconazole | 0.016–0.12 | 0.03–0.5 | 0.03 | 0.12 | 0.12 | 0.25 | 0 | 0 | |
| Fluconazole | ≤0.25–32 | ≤0.25–32 | 0.5 | 0.5 | 2 | 7 | 0 | 0 | |
| C. krusei (15) | Amphotericin B | 0.5–1 | 0.5–8 | 0.5 | 2 | 1 | 4 | 0 | 47 |
| Flucytosine | 2–8 | 4–32 | 8 | 16 | 8 | 16 | 0 | 7 | |
| Itraconazole | 0.12–1 | 0.25–2 | 0.25 | 0.5 | 0.5 | 1 | 7 | 47 | |
| Fluconazole | 8–64 | 16–128 | 16 | 64 | 64 | 128 | 13 | 53c | |
a
Inhibitory concentrations were determined spectrophotometrically by a microdilution method: ≥90% decrease in turbidity for amphotericin B and ≥50% decrease in turbidity for flucytosine, itraconazole, and fluconazole. 50% and 90%, MICs at which 50 and 90% of isolates were inhibited, respectively.
b
Defined as follows: amphotericin B resistance, ≥2 μg/ml at 24 h and ≥4 μg/ml at 48 h; flucytosine resistance, ≥32 μg/ml; itraconazole resistance, ≥1.0 μg/ml; and fluconazole resistance, ≥ 64 μg/ml.
c
Isolates of C. krusei were considered resistant to fluconazole irrespective of the MIC.