Antifungal Susceptibility Patterns,In VitroProduction of Virulence Factors, and Evaluation of Diagnostic Modalities for the Speciation of PathogenicCandidafrom Blood Stream Infections and Vulvovaginal Candidiasis

Abstract

Candida spp. have emerged as successful pathogens in both invasive and mucosal infections. Varied virulence factors and growing resistance to antifungal agents have contributed to their pathogenicity. We studied diagnostic accuracy of HiCrome Candida Differential Agar and Vitek 2 Compact system for identification of Candida spp. in comparison with species-specific PCR on 110 clinical isolates of Candida from blood stream infections (54, 49%) and vulvovaginal candidiasis (56, 51%). C. albicans (61%) was the leading pathogen in VVC, while C. tropicalis (46%) was prominent among BSIs. HiCrome Agar and Vitek 2 Compact had good measures of agreement (κ) 0.826 and 0.895, respectively, in comparison with PCR. We also tested these isolates for in vitro production of proteinase, esterase, phospholipases, and biofilms. Proteinase production was more among invasive isolates (P = 0.017), while phospholipase production was more among noninvasive isolates (P = 0.001). There was an overall increase in the production of virulence factors among non-albicans Candida. Identification of clinical isolates of Candida up to species level either by chromogenic agar or by Vitek 2 Compact system should be routinely done to choose appropriate therapy.

Prevalence, virulence factors and antifungal susceptibility ofCandidaspp. isolated from bloodstream infections in a tertiary care hospital in Brazil

“…Virulence factor production is of pivotal importance for candidemia establishment in the host. Enzyme production varies among Candida species and isolation sites . Erythrocyte lysis by haemolysins allows Candida spp.…”

“…Both C. albicans and NCA species can produce these virulence factors. However, information concerning NCA species is scarce because most studies have focused on C. albicans …”

Antifungal activity of cathelicidin peptides against planktonic and biofilm cultures of Candida species isolated from vaginal infections

“…In this respect, C. albicans strains isolated both from blood and mucosa showed similar in vitro biofilm formation capacity, without significant difference between invasive and non invasive isolates, despite high intra-species variability [31,71]. Concerning gynecological infections, C. albicans and other Candida spp., isolated from VVC patients, displayed in vitro the ability to adhere both to the plastic of microtiter plates and to the surface of intrauterine contraceptive devices, producing biofilm to different extents [11,56,57].…”

Perfil fenotípico e genotípico de isolados de Candida spp. em episódios de candidemia no Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto - FMRP-USP

“…pelo organismo. Esse fato, aliado ao uso de antibióticos de amplo espectro, que alteram a microbiota e favorecem o aumento de Candida spp., aumentam os riscos do paciente adquirir candidemia (SARDI et al, 2013 Além disso, isolados de hemocultura tendem a apresentar maior produção desses fatores que isolados de outros sítios anatômicos (DE LUCA et al, 2012;TELLAPRAGADA et al, 2014). Muitos isolados também apresentam capacidade de formação de biofilmes (SARDI et al, 2013).…”

“…As enzimas hidrolíticas extracelulares estão envolvidas na aquisição de nutrientes durante o estabelecimento da infecção, penetração e destruição dos tecidos do hospedeiro (ZICCARDI et al, 2015 A produção desses fatores de virulência, como dito anteriormente, varia entre as espécies e entre isolados de uma mesma espécie, sendo que isolados de sangue são relacionados com uma produção mais intensa desses em comparação com isolados de outros sítios anatômicos (DE LUCA et al, 2012;TELLAPRAGADA et al, 2014). …”