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

DUDIUDK, GARCÍA- EFFRÓN G; VIGEZZI C, DUDIUK C, ICELY PA, RODRÍGUEZ E, MIRÓ MS, ABIEGA C, CAEIRO JP, RIERA F, GARCIA-EFFRON G, SOTOMAYOR CE.

Santiago de Chile

Congreso; XIV Forum on Fungal Infection in the Clinical Practice, INFOCUS 2016 and XIX Immunocompromised Host Society Symposium,; 2016

Introduction. In recent years, Candida species have emerged as an important cause of invasive infections mainly among immunocompromised patients. When the fungus enters the blood stream it can invade deep tissues and organs, causing significant morbidity and mortality. Early reports showed that the classification of the main Candida spp (C.albicans, C.parapsilosis and C.glabrata) has been changed due to the description of new closely-related species, known as cryptic species. C. parapsilosis complex was divided into three groups, based on molecular typing with specific primers: C.parapsilosis sensu stricto, C.orthopsilosis, and C.metapsilosis, the first being the most prevalent.GoalsIn this study we analyzed the local frequency of the different Candida spp. from blood stream 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 capacity (BFC) and antifungal susceptibility of these 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) CLSI (doc m27a3 y s4) 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 were classified as Weak (Absorbance (A)