Phenotypic and genotypic detection of Candida albicans and Candida dubliniensis strains isolated from oral mucosa of AIDS pediatric patients

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Date
2017Author
Liverio, Harisson Oliveira
Ruiz, Luciana da Silva
de Freitas, Roseli Santos
Nishikaku, Angela Satie [UNIFESP]
de Souza, Ana Clara
Paula, Claudete Rodrigues
Domaneschi, Carina
Type
ArtigoISSN
0036-4665Is part of
Revista Do Instituto De Medicina Tropical De Sao PauloDOI
10.1590/S1678-9946201759014Metadata
Show full item recordAbstract
The aim of this study was to assess a collection of yeasts to verify the presence of Candida dubliniensis among strains isolated from the oral mucosa of AIDS pediatric patients which were initially characterized as Candida albicans by the traditional phenotypic method, as well as to evaluate the main phenotypic methods used in the discrimination between the two species and confirm the identification through genotypic techniques, i.e., DNA sequencing. Twenty-nine samples of C. albicans isolated from this population and kept in a fungi collection were evaluated and re-characterized. In order to differentiate the two species, phenotypic tests (Thermotolerance tests, Chromogenic medium, Staib agar, Tobacco agar, Hypertonic medium) were performed and genotypic techniques using DNA sequencing were employed for confirmation of isolated species. Susceptibility and specificity were calculated for each test. No phenotypic test alone was sufficient to provide definitive identification of C. dubliniensis or C. albicans, as opposed to results of molecular tests. After amplification and sequencing of specific regions of the 29 studied strains, 93.1% of the isolates were identified as C. albicans and 6.9% as C. dubliniensis. The Staib agar assay showed a higher susceptibility (96.3%) in comparison with other phenotypic techniques. Therefore, genotypic methods are indispensable for the conclusive identification and differentiation between these species.
Citation
Revista Do Instituto De Medicina Tropical De Sao Paulo. Sao Paulo, v. 59, p. -, 2017.Sponsorship
Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)Collections
- EPM - Artigos [17701]