Distribution, virulence factors and antifungal susceptibility patterns of Candida parapsilosis cryptic species isolated from patients with candidemia from Argentina´s Central region

VIGEZZI, CECILIA; ICELY, PAULA ALEJANDRA; DUDIUK, CATIANA; RODRIGUEZ, EMILSE; MIRÓ, MARÍA SOLEDAD; CASTILLO, GRACIELA; AZCURRA, ANA ISABEL; CAEIRO, JUAN PABLO; RIERA, FERNANDO OSCAR; GARCÍA EFFRON, GUILERMO; SOTOMAYOR, CLAUDIA ELENA

Congreso; 18th International Congress on Infectious Disease; 2018

A significant increase in invasive candidiasis caused by species different from C.albicans has been reported. C.parapsilopsis complex include three cryptic species: C parapsilosis sensu stricto, C. orthopsilosis and C. metapsilosis. These species differ in virulence and antifungal susceptibility. Adherence factors are crucial for fungal colonization; biofilms are related with persistence and hydrolytic enzyme production with invasion and damage.Our aims were to determine the prevalence of C.parapsilopsis sensu lato in patients with candidemia from Argentina´s central region, to evaluate the distribution of cryptic species and to establish differences in their virulence factor and antifungal susceptibility profiles.Materials and methods.35 candidemia patients from Cordoba city hospitals, were included. Yeasts isolated from bloodstream were molecularly identified to cryptic species level by using ribosomal operon sequences and a PCR-based restriction endonuclease analysis. Virulence factors studies included: Adherence by cell surface hydrophobicity assay (CSH); biofilm formation capacity(BFC) by XTT reduction method; aspartyl proteinase(Sap) by albumin-agar plate and Lipase by Rhodamine-B assay. Antifungal susceptibility testing was performed by using the CLSI documents M27A3/S4 and six antifungal drugs were evaluated including: voriconazole, posaconazole, itraconazole, amphotericin-B, caspofungin and anidulafungin.ResultsC.albicans was the most prevalent species (48.57%) followed by C. parapsilosis sensulato(28,57%). Molecular identification showed that 40% of the C.parapsilopsis sensu lato were in fact C.ortopsilopsis (no C. metapsilosis were isolated). Virulence factor study showed that CSH was similar in both cryptic species; C.parapsilopsis sensu-stricto exhibited strong BFC (0.570