Premium
Fungicidal activity and morphological alterations of Candida albicans induced by echinocandins: study of strains with reduced caspofungin susceptibility
Author(s) -
Dunyach Catherine,
Drakulovski Pascal,
Bertout Sébastien,
Jouvert Sylvie,
Reynes Jacques,
Mallié Michèle
Publication year - 2011
Publication title -
mycoses
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.13
H-Index - 69
eISSN - 1439-0507
pISSN - 0933-7407
DOI - 10.1111/j.1439-0507.2009.01834.x
Subject(s) - caspofungin , echinocandins , echinocandin , candida albicans , microbiology and biotechnology , strain (injury) , minimum inhibitory concentration , corpus albicans , biology , lysis , antifungal drug , in vitro , antifungal , amphotericin b , antibiotics , biochemistry , fluconazole , anatomy
Summary Caspofungin is a member of the echinocandin class of antifungal compounds that inhibit 1,3‐β‐ d ‐Glucan synthase. As patient exposure to caspofungin (CAS) broadens, the number of infecting strains with reduced susceptibility to this drug is expected to rise. In the present study, the in vitro effects of varying concentrations of CAS against Candida albicans isolates presenting reduced susceptibility to CAS were studied in comparison with a reference strain. Two C. albicans isolates presenting high minimal inhibitory concentrations (MIC = 8 μg ml −1 ) were selected: one isolate obtained in the laboratory under continuous antifungal selection pressure (CaIn‐R) and one clinical isolate (CaClin‐R) from a patient with a therapeutic failure. Results showed that after 24 h of CAS exposure, CaIn‐R and CaClin‐R presented a partial growth inhibition in comparison with the reference strain. Moreover, scanning electron microscopy and transmission electron microscopy studies showed that the cell walls of CaIn‐R and CaClin‐R were less altered than that of the reference strain. These observations suggested that although CaIn‐R and CaClin‐R cells were misshapen after CAS exposure, cell lysis was limited after 24 h of treatment indicating higher survival ability for CaIn‐R and CaClin‐R in the presence of CAS.