Prevalence and antifungal drug sensitivity of non-albicans Candida in oral rinse samples of self-caring elderly

Abstract

To assess the prevalence and antifungal drug sensitivity of non-albicans Candida (NAC) species in elderly outpatients. We investigated oral rinse samples of 194 self-caring elderly population (mean age 83 years) with emphasis on background factors for harbouring NAC. Susceptibility of Candida species to antifungal drugs was determined using standard methodology. Multiple logistic regression analysis was performed taking positive NAC count as the dependent variable and a number of known Candida risk factors as independent variables. Prevalence of candidal carriage of the population was 78.4%, of which 0.5% of the subjects were NAC positive. Candida dubliniensis was the most prevalent NAC species, followed by Candida glabrata and Candida parapsilosis. The NAC positive elderly were more often edentulous with dental prostheses or had fewer teeth than Candida albicans-positive or yeast-negative subjects. Dental caries slightly increased the risk for having NAC strains (odds ratio 1.08), whilst greater age appeared to lower the risk (odds ratio 0.77). Candida species were susceptible to the commonly used antifungal agents in general, but with considerable variation among species. Occasionally, some NAC exhibited lower antifungal susceptibility. The possibility of oral reservoirs of NAC strains which are resistant to common antifungals should be noted in elderly outpatients.