Dynamics of in vitro acquisition of resistance by Candida parapsilosis to different azoles

• Type: Article in International Scientific Journal
• Date: 2009

Authors

silva, atpe (Author) Other; costa-de-oliveira, s (Author) FMUP; silva-dias, a (Author) Other; pina-vaz, c (Author) FMUP; rodrigues, ag (Author) FMUP

Journal

Title: FEMS Yeast Research

Vol. 9

Pages: 626-633

ISSN: 1567-1356

Publisher: Oxford University Press

Indexing

ISI Web of Knowledge - 26 Citations

Scopus - 30 Citations

Scientific classification

FOS: Natural sciences > Biological sciences

Other information

Authenticus ID: P-003-JGK

DOI: 10.1111/j.1567-1364.2009.00508.x

Abstract (EN): Candida parapsilosis is a common isolate from clinical fungal infectious episodes. Resistance of C. parapsilosis to azoles has been increasingly reported. To analyse the development of resistance in C. parapsilosis, four azole-susceptible clinical strains and one American Type Culture Collection type strain were cultured in the presence of fluconazole, voriconazole and posaconazole at different concentrations. The isolates developed variable degrees of azole resistance according to the antifungal used. Fluconazole was the fastest inducer while posaconazole was the slowest. Fluconazole and voriconazole induced resistance to themselves and each other, but not to posaconazole. Posaconazole induced resistance to all azoles. Developed resistance was stable; it could be confirmed after 30 days of subculture in drug-free medium. Azole-resistant isolates revealed a homogeneous population structure; the role of azole transporter efflux pumps was minor after evaluation by microdilution and cytometric assays with efflux pump blockers (verapamil, ibuprofen and carbonyl cyanide 3-chloro-phenylhydrazone). We conclude that the rapid development of azole resistance occurs by a mechanism that might involve mutation of genes responsible for ergosterol biosynthesis pathway, stressed by exposure to antifungals.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 8