Comparative In Vitro Susceptibility of Clinical Isolates of Candida parapsilosis Complex and Other Candida Species to Caspofungin and Anidulafungin by Etest

Abstract

In Vitro susceptibility of 141 clinical isolates of Candida species to caspofungin and anidulafungin is reported. The Etest was performed according to recommended procedure and minimum inhibitory concentrations (MICs) were read after 24 h of incubation at 35°C. Applying a breakpoint of ≤2 μg/ml, all Candida spp. isolates, except those belonging to C. parapsilosis complex, were susceptible. The geometric mean for caspofungin and anidulafungin for different Candida spp. were as follows: Candida parapsilosis, 0.438 and 3.355 μg/ml; Candida orthopsilosis, 0.210 and 1.456 μg/ml; Candida albicans, 0.049 and 0.007 μg/ml; Candida dubliniensis, 0.077 and 0.009 μg/ml; Candida tropicalis, 0.061 and 0.027 μg/ml; Candida glabrata, 0.120 and 0.032 μg/ml; and Candida krusei, 0.288 and 0.052 μg/ml, respectively. Anidulafungin was significantly more active than caspofungin (p <0.001) except for C. parapsilosis complex spp. isolates. In conclusion, our Etest MICs compared well with epidemiological cutoff values derived from a large number of Candida spp. isolates tested by CLSI method in previous studies. However, considering the differences in MICs of the two echinocandins for C. parapsilosis complex isolates, the Etest needs further evaluation for its suitability.