Isavuconazole activity against Candida species from Brazil focusing on C. auris: MIC comparison between EUCAST and CLSI.

AIM: We evaluated the in vitro activity of isavuconazole against different Candida clinical species from Brazil, with an emphasis on C. auris, using CLSI and EUCAST, and compared the results to expand the literature on this new triazole.

METHODS

A total of 102 strains of Candida spp. were isolated from critically ill patients admitted to tertiary hospitals in Recife, Pernambuco, Brazil. All isolates were identified using MALDI-TOF MS and tested using broth microdilutions.

RESULTS

The species identified were C. auris (62), C. albicans (14), C. tropicalis (9), C. parapsilosis (5), C. glabrata (3), C. metapsilosis, C. orthopsilosis (2) each, C. duobushaemulonii, Meyerozyma guilliermondii, Clavispora lusitaniae, C. nivariensis, and Wickerhamomyces anomolus (1). A modal MIC90 of ≤0.008 µg/mL and a wild-type modal upper limit value of <0.03 µg/mL were found. Thus, 99.1% (CLSI) and 95.1% (EUCAST) of the strains were wild-type. The overall essential agreement rate between the methods was 95.1% (±2 log2 dilutions) and 89.2% (±1 log2 dilution).

CONCLUSION

Both methodologies were useful for evaluating the antifungal potential of isavuconazole and highlighted the low MICs of this triazole against the Brazilian collection of Candida spp., especially the emerging yeast C. auris.