Comparison of Etest and NCCLS M38-P Methods for Testing Susceptibilities of Aspergillus spp. to Posaconazole


Author address: 

1Med. Coll. of Virginia of Virginia Commonwealth Univ, Richmond, VA, Richmond, VA, 2Facultad Huesca, Zaragoza, Spain.


Background: The NCCLS has proposed standard testing guidelines (NCCLS M38-P document) for the susceptibility testing of filamentous fungi (moulds). However, the M38-P methods are time-consuming and cumbersome and Etest and NCCLS methods provide comparable results for the established agents. The purpose of this study was to compare M38-P and Etest MICs of the novel triazole posaconazole (P) for Aspergillus spp. Methods: Broth microdilution and Etest MICs of P, amphotericin B (A) and itraconazole (I) were obtained simultaneously for 103 isolates (6-62 per species) of A. flavus, A. fumigatus, A. nidulans, A. niger, and A. terreus, which included I-resistant strains. Etest MICs were determined on solidified (1.5% agar) RPMI-1640 (2% dextrose) after both 24 and 48 h of incubation. M38-P MICs were the lowest drug dilutions that showed 100% inhibition after 48 h of incubation. Results: Overall, Etest MICs of P were

abstract No: 


Full conference title: 

ICAAC 41st
    • ICAAC 41st