Resumo

Oral candidiasis is the most frequently observed opportunistic infection in HIV-positive patients, about 60% to 95% of these individuals develop this infection. It is often detected in recurrent episodes, especially when the count of CD4⁺ T cells is at low levels. Several studies have reported that the virulence factors in yeast provide mechanisms evolved in their pathogenesis. The aim of this study was to determine the profile of cell surface hydrophobicity, biofilm production and the percentage and size of germ tube (GT) formed by C. albicans isolated from oral cavity of HIV-positive and HIV-negative patients. The pattern at ultrastructural level (SEM analysis) of in vitro adherence of yeasts in acrylic resins with and without finishing and polishing was also evaluated. A total of 07 C. albicans isolates were used, 03 isolates of each group (HIV-positive patients and HIV-negative patients) and a standard strain C. albicans ATCC 90028. The yeasts identification were by standard methods and confirmed by PCR assay. A correlation between the isolates of the same group was observed regarding the virulence factors studied. Isolates obtained from HIV-positive patients exhibited hydrophilic profiles (96.30%) corresponding to the biofilm production method of Shin (1+) while the results of HIV-negative individuals showed tendency of hydrophobic profile (47.65%) correlating to the biofilm production (4+). The isolates of HIV-positive and HIV-negative patients differed in their ability to produce TG. Although in both groups occurred variation in the percentage of cells that have differentiated (8.5% to 38%) and the length of the same (15.78 to 49.05 µm), respectively, it was possible to observe a change in the pattern of adhesion and cellular differentiation among isolates in different dental materials revealed by SEM. There was great adherence capacity of the isolates in acrylic resins without finishing and polishing. The data corroborate the idea of the variability of potential virulence of the yeast strains, and also, unlike other authors, that the infection in the oral cavity is more related to the condition of the patient immune system than the virulence attributes of yeast.