Candidemia: identification of cryptic species in Candida parapsilosis complex, distribution, antifungal susceptibility and biofilm forming capacity

VIGEZZI, CECILIA; DUDIUK, CATIANA; ICELY, PAULA ALEJANDRA; RODRIGUEZ, EMILSE; MIRÓ, MARÍA SOLEDAD; ABIEGA, CLAUDIO; CAEIRO, JUAN PABLO; RIERA, FERNANDO; GARCÍA EFFRON, GUILERMO; SOTOMAYOR, CLAUDIA ELENA

Santiago de Chile

Congreso; XIV Forum on Fungal Infection in the Clinical Practice; 2016

Introduction. In recent years, Candida species have emerged as important cause of invasive infections mainly among immunocompromised patients. When the organisms enter the blood stream they can invade deep tissues and organs, causing significantmorbidity and mortality.Early reports showed that the classification of the main Candida spp(C.albicans, C.parapsilosis and C.glabrata) has been changeddue to the description of new closely-related species, known ascryptic species. C. parapsilosiscomplexwas divided into three groups, based on molecular typing whit specific primers: C.parapsilosissensustricto, C.orthopsilosis, and C.metapsilosis, being the first the most prevalent.GoalsIn this study we analyzed the local frequency of the different species Candida spp. among bloodstream isolates and the distribution of species by age of the patient. Also, we evaluated the presence of cryptic strains of C.parapsilopsis complex by molecular biology and assessed the biofilm forming capcity (BFC) and antifungal susceptibility of this isolates.Materials and methods. 35 patients with candidemia from two local hospitals were studied. The yeasts were isolated from bloodstream and molecularly identified (ribosomal operon sequences). For the determination of minimum inhibitory concentration (MIC), EUCAST protocol was used. Quantitative measurement of biofilm formation was assessed by XTT reduction assay performed in triplicate for all strains and the averages and standard deviations were calculated for all experiments. Strains was classified as Weak (Absorbance (A) <0.310) (WBFC), Moderate (0.310