TABLE 1.
In vitro susceptibilities of 86 Aspergillus species isolates to azole antifungal agents as determined by the SYO methoda
| Species (no. of isolates tested) | Species complex or section | Antifungal agentc | No. of isolates (no. of mutantsb) with MIC (μg/ml) of: |
|||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ≤0.03 | 0.06 | 0.12 | 0.25 | 0.5 | 1 | 2 | 4 | 8 | >8 | |||
| Common species | ||||||||||||
| A. fumigatus (21) | Fumigati | PSC | 5 | 6 | 2 (2) | 8 (8) | ||||||
| VRC | 2 | 5 | 4 | 1 (1) | 1 (1) | 2 (2) | 1 (1) | 5 (5) | ||||
| ITC | 2 | 7 | 3 (1) | 4 (4) | 1 (1) | 4 (4) | ||||||
| A. flavus (19) | Flavi | PSC | 7 | 12 | ||||||||
| VRC | 1 | 14 | 3 | 1 | ||||||||
| ITC | 1 | 9 | 8 | 1 | ||||||||
| A. terreus (12) | Terrei | PSC | 9 | 3 | ||||||||
| VRC | 1 | 8 | 3 | |||||||||
| ITC | 3 | 8 | 1 | |||||||||
| A. niger (7) | Nigri | PSC | 1 | 2 | 1 | 3 | ||||||
| VRC | 6 | 1 | ||||||||||
| ITC | 2 | 3 | 2 | |||||||||
| Uncommon species | ||||||||||||
| A. tubingensis (6) | Nigri | PSC | 4 | 2 | ||||||||
| VRC | 1 | 5 | ||||||||||
| ITC | 3 | 3 | ||||||||||
| A. nidulans (5) | Nidulantes | PSC | 3 | 2 | ||||||||
| VRC | 2 | 3 | ||||||||||
| ITC | 4 | 1 | ||||||||||
| A. oryzae (5) | Flavi | PSC | 2 | 2 | 1 (1) | |||||||
| VRC | 2 | 2 | 1 (1) | |||||||||
| ITC | 3 | 1 | 1 (1) | |||||||||
| A. lentulus (3) | Fumigati | PSC | 2 | 1 | ||||||||
| VRC | 2 | 1 | ||||||||||
| ITC | 1 | 2 | ||||||||||
| A. (Neosartorya) species (3)d | Fumigati | PSC | 2 | 1 | ||||||||
| VRC | 1 | 1 | 1 | |||||||||
| ITC | 2 | 1 | ||||||||||
| A. foetidus (3) | Nigri | PSC | 2 | 1 | ||||||||
| VRC | 2 | 1 | ||||||||||
| ITC | 3 | |||||||||||
| A. awamori (2) | Nigri | PSC | 2 | |||||||||
| VRC | 2 | |||||||||||
| ITC | 1 | 1 | ||||||||||
MICs were determined visually after 48 h of incubation and were defined as the antifungal concentrations at which complete (100%) inhibition of growth of the Aspergillus species isolates was observed. As a prolonged incubation (i.e., >24 h) of SYO colorimetric plates was required, visual readings of MICs were performed regardless of color changes.
Mutant isolates were defined as isolates carrying a cyp51a mutation (e.g., a leucine-for-histidine substitution), together with a tandem repeat of a 34-bp (or 46-bp) sequence in the gene promoter that is known to be associated with azole resistance in A. fumigatus (4, 12). One of 5 A. oryzae isolates was found to carry the T788G mutation in the cyp51c gene that has been reported as an azole resistance mechanism in the closely related species A. flavus (22).
PSC, posaconazole; VRC, voriconazole; ITC, itraconazole.
Data include 1 isolate each of A. (Neosartorya) hiratsukae, A. thermomutatus (Neosartorya pseudofischeri), and A. (Neosartorya) udagawae. In accordance with the recent taxonomists' recommendations for species for which a single-name nomenclature (i.e., keeping the name Aspergillus for all species of this genus) must be applied (17), the old teleomorphic name is indicated in brackets.