The cross-resistance to azoles was demonstrated in C. parapsilosis, in vitro exposure to azoles, namely FLC and voriconazole (VRC), was shown to alter the susceptibility in C. parapsilosis, and resistance to these two azoles was developed after exposure to each of them, although surprisingly the susceptibility to posaconazole (PSC) was increased. Instead when C. parapsilosis was exposed to PSC the susceptibility was decreased to all azoles. In vivo and in vitro comparison of expression levels of genes involved in azole resistance of Candida parapsilosis

The studies conected on azole resistance by infectious fungi, capable of affecting human health, are carried out generally in an in vitro system. The expression levels of the target genes do not correlate directly with the MICs of the isolates. In many cases the discrimination of susceptibility or resistance to an antifungal drug was not possible analysing the transcription levels or possible mutations than can affect the protein structure of azoles target. For this reason, our study addresses the analysis of this mechanism of resistance in four clinical isolates of C. parapsilosis from a different point of view, the role of resistance in vivo. In vitro activity and in vivo efficacy of POS, itraconazole (ITC) and VRC against four clinical strains of C. parapsilosis was evaluated. Furthermore, in order to better understand the resistance profile of our isolates, analysis of mechanisms of resistance was carried out, mutations in gen ERG11 gene was searched and study of expressions levels of ERG11 and CDR1 in vitro and in vivo was performed.