Anidulafungine : activité in vitro sur les levures et les champignons filamenteux d'intérêt clinique

During its development, in vitro activity of anidulafungin, a new echinocandin, was studied against a large panel of clinically relevant species of micromycetes : yeasts (Candida species, Cryptococcus neoformans), filamentous fungi (Aspergillus species and others) and dimorphic fungi. Anidulafungin is active at very low concentrations and fungicidal against most Candida species, including those naturally resistant (Candida krusei) or with low sensibility (Candida glabrata) to other systemic antifungals, especially triazoles. Minimum inhibitory concentrations (MICs) for anidulafungin against almost 100 % of Candida krusei and Candida glabrata are very low (ranging from 0,12 μg/ml to 0,25 μg/ml). This property is important because, on one hand, proportion of candidemias due to C. glabrata is continuously increasing, and on the other hand, this species is associated with higher mortality in elderly patients, immunosuppressed patients and intensive care units patients, at least in some studies. Anidulafungin is also active against Candida lusitaniae, which is frequently resistant to amphotericin B. Concerning Aspergillus spp, anidulafungin is fungistatic in vitro against most Aspergillus species. However, anidulafungin is not active against species lacking echinocandins target enzyme, β-l,3-D-glucan synthase (Cryptococcus neoformans, Trichosporon sp, Fusarium sp, Zygomycetes) or species with genetic polymorphisms of this enzyme (Candida parapsilosis and Candida guilliermondii).