Antifungal susceptibility and virulence attributes of animal-derived isolates of Candida parapsilosis complex

Abstract

This study aimed to identify strains of the Candida parapsilosis complex isolated from animals, as well as to assess their in vitro antifungal susceptibility profile and in vitro production of virulence attributes. We used 28 isolates of C. parapsilosis sensu lato recovered from clinically healthy animals. The strains were characterized phenotypically, followed by molecular identification of the species through PCR-restriction enzyme analysis. The susceptibility of the strains to amphotericin B, itraconazole, voriconazole, fluconazole and caspofungin was assessed through broth microdilution. Additionally, the ability of the strains to produce biofilm, phospholipases and proteases was analysed. Molecular analysis showed 13 C. parapsilosis sensu stricto, 10 Candida orthopsilosis and five Candida metapsilosis strains. In vitro resistance to fluconazole was observed in three strains of C. parapsilosis sensu stricto and two C. metapsilosis. All tested strains were able to form biofilms and 23/28 isolates presented protease production, whilst none was able to produce phospholipases. Our study showed that C. parapsilosis sensu stricto and C. orthopsilosis are the most common species of the C. parapsilosis species complex and that these cryptic species present no significant phenotypical differences.