Table 1.
Main parameters for the performance of the Clinical and Laboratory Standards Institute (CLSI) broth methods (M27-A3 and M27-S4 documents) (with European Committee on Antibiotic Susceptibility Testing (EUCAST) modifications) and disk diffusion method (M44-A and M44-S2 documents) for yeasts. Data from Arikan (2007) [28] and Canton et al. (2009) [27].
| Parameter | Broth-Method | Disk-Diffusion Method |
|---|---|---|
| Test medium | Roswell Park Memorial Institute Medium (RPMI-1640) with glutamine, without bicarbonate. Glucose concentration: 0.2% (EUCAST 2%) | Mueller-Hinton agar + 2% glucose + 0.5 mg/L methylene blue |
| Inoculum size | 0.5 × 103–2.5 × 103 CFU/mL (EUCAST 1 × 105–5 × 105) |
0.5 Mc Farland standard (1 × 106 to 5 × 106 CFU/mL) |
| Microdilution plates | 96 U-shaped wells (EUCAST flat-bottom wells) | NA |
| Temperature and incubation time |
Candida spp., 48 h a at 35 °C (EUCAST 24 h) Cryptococcus neoformans, 72 h at 35 °C |
35 °C for 20–24 h Some strains of Candida glabrata, Candida krusei, and Candida parapsilosis often require 48 h |
| Reading method | Visual (EUCAST Spectrophotometric 530 nm) | Measurement of zone size |
a = Reading at 24 h is acceptable, provided that fungal growth is adequate, for amphotericin B, and fluconazole. Echinocandins must be read at 24 h; NA = not applicable.