Biofilm production in oral Candida isolates from HIV-positive individuals from Pune, India

Biofilm formation is implicated as a potential virulence factor in Candida species and carries important clinical repercussions because of their increased resistance to antifungal treatment, ability to withstand host defences and to serve as a reservoir for continuing infections. The present study was undertaken to determine the biofilm production among oral Candida isolates from HIV-positive and HIV-negative individuals from Pune, India. Biofilm formation was determined using the spectrophotometric or microtitre plate method in 182 Candida isolates, of which 154 were from HIV-positive and 28 were from HIV-negative individuals. A total of 63.2% of the Candida isolates were biofilm producers. Significantly increased biofilm forming abilities both qualitatively as well as quantitatively were observed in Candida isolates from HIV-positive individuals (66.2%) compared to isolates from HIV-negative ones (46.4%), (P 0.041). Eighty-one (59.6%) C. albicans isolates and 34 (73.9%) non C. albicans Candida (NCAC) showed biofilm positivity. The NCAC showed significantly greater intensity of biofilm formation compared to the C. albicans, P 0.032. Our results thus show the enhanced biofilm forming abilities of oral Candida isolates from HIV-infected individuals compared to HIV-uninfected ones and highlight the important role played by biofilm formation in the pathogenesis of NCAC isolates.