Colonization of the oral cavity by yeasts in patients with chronic renal failure undergoing hemodialysis

Abstract

To determine the frequency of yeast in the oral cavity of patients with chronic renal failure, undergoing hemodialysis (PCRFH); identification and antifungal susceptibility profile of yeast and demographic profile of patients. We performed mouthwash in 146 PCRFH; the rinse fluid was collected and cultured, yeasts grown were identified by phenotypic and molecular methods. The antifungal susceptibility profile was determined against nystatin, amphotericin B, fluconazole, voriconazole, and caspofungin based in Clinical and Laboratory Standards Institute (document M27-A3). Positive culture was observed in 39% of patients, of whom 53% were women; the median of dialysis time was 2.9 years. The age of the colonized patients varied between 26 and 84 years, with a median of 52.5 years. PCRFH over 45 years were significantly more colonized (P = 0.0108) as well as denture wearers (84.0%). We isolated 81 yeasts, predominantly Candida albicans (63%) followed by Candida glabrata. In general, yeasts were sensitive to the evaluated antifungal agents, but there was significant variation in the minimum inhibitory concentration, especially among non-C. albicans Candida (NCAC) compared to fluconazole, caspofungin, and amphotericin B. NCAC required significantly higher concentrations of fluconazole (P < 0.01). The rate of colonization by yeasts in PCRFH was high, and there was variability in species distribution and antifungal susceptibility profile. These results are little known in this group of patients and are important for controlling the risk of developing invasive fungal infections.