Related Experiment Video
Updated: Jul 30, 2026
A 96 Well Microtiter Plate-based Method for Monitoring Formation and Antifungal Susceptibility Testing of Candida albicans Biofilms
Published on: October 21, 2010
In vitro susceptibility testing of filamentous fungi: comparison of Etest and reference M38-A microdilution methods
M A Pfaller1, S A Messer, L Boyken
1Department of Pathology, University of Iowa College of Medicine, Iowa City, IA 52242, USA. michael-pfaller@uiowa.edu
Abstract:
The performance of the Etest for posaconazole susceptibility testing of 72 isolates of filamentous fungi was assessed in comparison with the National Committee for Clinical Laboratory Standards (NCCLS) approved standard broth microdilution method (M38-A). The NCCLS method employed RPMI 1640 broth medium, and MICs were read after incubation for 48h at 35 degrees C. Etest MICs were determined with RPMI agar containing 2% glucose and were read after incubation for 48h at 35 degrees C. The isolates included Aspergillus fumigatus, A. flavus, A. nidulans, A. niger, A. versicolor, A. oryzae, A. terreus, Cladosporium spp., Curvularia sp., Exophiala sp., Fusarium spp., Paecilomyces spp., Pithomyces sp., Penicillium spp. and Scedosporium apiospermum. Overall agreement between Etest and microdilution MICs was 84% for Aspergillus spp. and 100% for the less common opportunistic molds, with the exception of Penicillium spp. (67%). Where a discrepancy was observed between Etest and the reference method, the Etest tended to give lower values. The Etest method using RPMI agar appears to be a useful method for determining posaconazole susceptibilities of filamentous fungi.
