Evaluation of a modified EUCAST fragmented-mycelium inoculum method for in vitro susceptibility testing of dermatophytes and the activity of novel antifungal agents

B Risslegger; C Lass-Flörl; G Blum; M Lackner

doi:10.1128/AAC.04381-14

Evaluation of a modified EUCAST fragmented-mycelium inoculum method for in vitro susceptibility testing of dermatophytes and the activity of novel antifungal agents

Antimicrob Agents Chemother. 2015;59(6):3675-82. doi: 10.1128/AAC.04381-14. Epub 2015 Apr 13.

Authors

B Risslegger¹, C Lass-Flörl¹, G Blum¹, M Lackner²

Affiliations

¹ Department of Hygiene, Microbiology and Social Medicine, Division of Hygiene and Medical Microbiology, Medical University of Innsbruck, Innsbruck, Austria.
² Department of Hygiene, Microbiology and Social Medicine, Division of Hygiene and Medical Microbiology, Medical University of Innsbruck, Innsbruck, Austria [email protected].

Abstract

For antifungal susceptibility testing of nonsporulating or poorly sporulating dermatophytes, a fragmented-mycelium inoculum preparation method was established and compared to broth microdilution testing according to CLSI and EUCAST guidelines. Moreover, the in vitro activity of new antifungal agents against dermatophytes was evaluated. Agreement between the mycelial inoculum method and the CLSI broth microdilution method was high (93% to 100%). Echinocandins (minimal effective concentration [MEC], ≤0.5 mg/liter) and posaconazole (MIC, ≤3.00 mg/liter) showed good activity against all tested dermatophytes.

MeSH terms

Antifungal Agents / pharmacology*
Echinocandins / pharmacology
Microbial Sensitivity Tests / methods*
Mycelium / drug effects*
Triazoles / pharmacology
Trichophyton / drug effects

Substances

Antifungal Agents
Echinocandins
Triazoles
posaconazole