Abstract

We selected voriconazole-resistant (VCZ-R) Aspergillus fumigatus in the laboratory, characterized the cyp51A gene for possible mutations and evaluated the in vitro activities of voriconazole and anidulafungin alone and in combination against VCZ-R isolates of A. fumigatus using a fractional inhibitory concentration index (FICI) methodology. Voriconazole-resistant isolates were selected from wild-type A. fumigatus isolates in the laboratory by a 2-step selection process (plus 1 clinical isolate). The MICs of azoles (VCZ, posaconazole, itraconazole) and echinocandins (anidulafungin, micafungin, and caspofungin) for all A. fumigatus isolates were then determined in RPMI1640 using the broth microdilution technique recommended by the Clinical Laboratory and Standards Institute M38-A2 methodology and the FICI calculated. The combination of VCZ and anidulafungin was synergistic (FICI <0.5) not only against VCZ-susceptible isolates, but also against 8 of 10 VCZ-R, G448S mutants of A. fumigatus. The combination demonstrated synergy against the VCZ-R clinical isolate as well.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.