We evaluated the newly proposed agar screening method for echinocandin susceptibility testing of 144 Aspergillus section Terrei isolates compared with the Etest method. Both methods defined the isolates to be wild-type strains for anidulafungin and micafungin, with Etest minimal effective concentrations (MECs) of ≤0.004 mg/L. For caspofungin, the novel agar screening method identified 37 isolates to be caspofungin non-wild type based on their fluffy colony appearance on caspofungin agar. Etest MECs for caspofungin for these isolates were scattered widely from 0.002 to 0.750 mg/L, showing only partial accordance between the two methods.
Keywords: Aspergillus terreus; agar screening method; antifungal susceptibility testing; echinocandins.