FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / In recent years there has been a significant increase in the incidence of fungal infections caused by Candida species. Although C. albicans be considered the principal representing of the genus, other species have been gaining prominence. C. tropicalis, for example, has been associated with serious invasive cadidiases, being the first or second type of non-Candida albicans Candida most commonly isolated in humans with candidemia and candiduria and is frequently isolated from healthy animals and animals with candidiasis. To establish infection, C. tropicalis expresses many virulence factors such as the secretion of enzymes phospholipases and proteases, biofilm production, among others. This study aimed to evaluate the in vitro antifungal susceptibility profile and production of virulence factors in strains of C. tropicalis (n=100) isolated from several animal species. The strains were subjected to in vitro susceptibility testing by broth microdilution test, M27-A3 protocol, standardized by the Clinical and Laboratory Standards Institute against amphotericin B, itraconazole and fluconazole. We also evaluated the virulence attributes, such as proteases and phospholipases production and biofilm formation. Regarding the susceptibility of C. tropicalis strains, 38% were resistant to itraconazole, 40% were resistant to fluconazole and 34% were resistant to both azoles. None of the strains were resistant to amphotericin B. Regarding the production of proteases, 84% of the strains secreted these enzymes in the medium with pH 5.0, whereas only 40% of the strains were active at pH 3.5. Only 8% of the strains produced phospholipases. The strains showed different pattern in biofilm production, which 63,2% were strong producers, 17,6% were moderate producers, and 13,3% were weak producers. In sumary, the C. tropicalis strains isolated from animals showed high rate of resistance to azoles and expressed important virulence factors, indicating a potential threat to human and animal health. / Nos Ãltimos anos houve um aumento significativo na incidÃncia de infecÃÃes fÃngicas causadas por leveduras do gÃnero Candida. Apesar de C. albicans ser considerada a principal representante do gÃnero, outras espÃcies vÃm ganhando destaque. C. tropicalis, por exemplo, tem sido associada à cadidÃases invasivas graves, sendo a primeira ou segunda espÃcie de Candida nÃo-albicans mais comumente isolada em candidemia e candidÃria em humanos, alÃm de ser frequentemente isolada da microbiota de animais saudÃveis e com candidÃase. Para estabelecer a infecÃÃo, C. tropicalis expressa diversos fatores de virulÃncia, como a secreÃÃo de enzimas protease e fosfolipase, a produÃÃo de biofilme, dentre outros. O presente trabalho buscou avaliar o perfil de sensibilidade antifÃngica in vitro e produÃÃo de fatores de virulÃncia de cepas de C. tropicalis (n=100) isoladas de diferentes espÃcies animais. As cepas foram submetidas a teste de sensibilidade in vitro por meio do mÃtodo de microdiluiÃÃo em caldo, protocolo M27-A3, padronizado pelo Clinical and Laboratory Standards Institute, frente anfotericina B, itraconazol e fluconazol. Foram avaliados ainda os atributos de virulÃncia: produÃÃo de enzimas proteases e fosfolipases e produÃÃo de biofilme. Quanto ao perfil de sensibilidade das cepas de C. tropicalis, 38% foram resistentes a itraconazol, 40% resistentes a fluconazol e 34% foram resistentes a ambos os derivados azÃlicos. Nenhuma cepa apresentou resistÃncia a anfotericina B. Quanto a produÃÃo de proteases, 84% das cepas secretaram estas enzimas em meio com pH 5,0, enquanto somente 40% das cepas foram ativas em pH 3,5. Somente 8% das cepas produziram fosfolipases. As cepas apresentaram padrÃo diferenciado na produÃÃo de biofilme, em que 63,2% foram consideradas fortes produtoras, 17,6% foram consideradas moderadas produtoras e 13,3% foram consideradas fracas produtoras. Em suma, os isolados de C. tropicalis provenientes de animais apresentaram resistÃncia a derivados azÃlicos e expressaram fatores de virulÃncia importantes, indicando potencial risco à saÃde humana e animal.
| Identifer | oai:union.ndltd.org:IBICT/oai:www.teses.ufc.br:9846 |
| Date | 19 December 2013 |
| Creators | Jonathas Sales de Oliveira |
| Contributors | Rossana de Aguiar Cordeiro, Nilberto Robson FalcÃo do Nascimento, Marcos FÃbio Gadelha Rocha, Camila Gomes VirgÃnio Coelho |
| Publisher | Universidade Federal do CearÃ, Programa de PÃs-GraduaÃÃo em Microbiologia MÃdica, UFC, BR |
| Source Sets | IBICT Brazilian ETDs |
| Language | Portuguese |
| Detected Language | English |
| Type | info:eu-repo/semantics/publishedVersion, info:eu-repo/semantics/masterThesis |
| Format | application/pdf |
| Source | reponame:Biblioteca Digital de Teses e Dissertações da UFC, instname:Universidade Federal do Ceará, instacron:UFC |
| Rights | info:eu-repo/semantics/openAccess |
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