Activities of antifungal agents against yeasts and filamentous fungi: assessment according to the methodology of the European Committee on Antimicrobial Susceptibility Testing.
We compared the activities of antifungal agents against a wide range of yeasts and filamentous fungi. The methodology of the European Committee on Antimicrobial Susceptibility Testing (EUCAST) for yeasts and spore-forming molds was applied; and a total of 349 clinical isolates of Candida spp., other yeast species, Aspergillus spp., and nondermatophyte non-Aspergillus spp. were investigated. The average geometric mean (GM) of the MICs of the various drugs for Candida spp. were as follows: amphotericin B (AMB), 0.55 microg/ml; liposomal amphotericin B (l-AMB); 0.35 microg/ml; itraconazole (ITC), 0.56 microg/ml; voriconazole (VRC), 0.45 microg/ml; posaconazole (POS), 0.44 microg/ml; and caspofungin (CPF), 0.45 microg/ml. The data indicated that the majority of Candida spp. were susceptible to the traditional and new antifungal drugs. For Aspergillus spp., the average GM MICs of AMB, l-AMB, ITC, VRC, POS, and CPF were 1.49 microg/ml, 1.44 microg/ml, 0.65 microg/ml, 0.34 microg/ml, 0.25 microg/ml, and 0.32 microg/ml, respectively. For the various zygomycetes, the average GM MICs of AMB, l-AMB, ITC, and POS were 1.36 microg/ml, 1.42 microg/ml, 4.37 microg/ml, and 1.65 microg/ml, respectively. Other yeastlike fungi and molds displayed various patterns of susceptibility. In general, the minimal fungicidal concentrations were 1 to 3 dilutions higher than the corresponding MICs. POS, AMB, and l-AMB showed activities against a broader range of fungi than ITC, VRC, and CPF did. Emerging pathogens such as Saccharomyces cerevisiae and Fusarium solani were not killed by any drug. In summary, the EUCAST data showed that the in vitro susceptibilities of yeasts and filamentous fungi are variable, that susceptibility occurs among and within various genera and species, and that susceptibility depends on the antifungal drug tested. AMB, l-AMB, and POS were active against the majority of pathogens, including species that cause rare and difficult-to-treat infections.
Lass-Flörl
Cornelia
C
Department of Hygiene, Microbiology and Social Medicine, Innsbruck Medical University, Fritz Pregl Str. 3, Innsbruck 6020, Austria. Cornelia.lass-floerl@i-med.ac.at
Mayr
Astrid
A
Perkhofer
Susanne
S
Hinterberger
Guido
G
Hausdorfer
Johann
J
Speth
Cornelia
C
Fille
Manfred
M
D000666:Amphotericin B / Q000494:pharmacology; D000935:Antifungal Agents / Q000494:pharmacology*; D001230:Aspergillus / Q000187:drug effects / Q000302:isolation & purification; D002175:Candida / Q000187:drug effects / Q000302:isolation & purification; D025141:Drug Resistance, Fungal; D005060:Europe; D005658:Fungi / Q000187:drug effects* / Q000302:isolation & purification; D017408:Guidelines as Topic; D006801:Humans; D008826:Microbial Sensitivity Tests / Q000379:methods* / Q000592:standards; D009181:Mycoses / Q000188:drug therapy / Q000382:microbiology; D009894:Opportunistic Infections / Q000188:drug therapy / Q000382:microbiology; D014230:Triazoles / Q000494:pharmacology; D015003:Yeasts / Q000187:drug effects* / Q000302:isolation & purification
D000935:Antifungal Agents; D014230:Triazoles; C101425:posaconazole; D000666:Amphotericin B