Oral Candida isolates and fluconazole susceptibility patterns in older Mexican women

• Oral candidiasis increased with age of 13.2–33.3% between 60 and >80 years.
• Frequency of colonizing the oral cavity increased with age.
• The frequency of oral colonization by multi-species of Candida increases with age.
• The oral Candida albicans isolates shows increased resistance to fluconazole with increasing age range in older Mexican women.

ObjectivesTo assess the epidemiologic and microbiologic profile and in vitro fluconazole susceptibility of yeasts isolated from the oral mucosa colonization/infection of elderly patients.BackgroundIt has been reported that in older adults increases the oral colonization by Candida particularly C. non-albicans, showing a decreased response to fluconazole, which increases the risk of recalcitrant local and disseminated candidiasis.Materials and methodsThis was a prospective cross-sectional study conducted in 120 elderly patients. Oral samples were obtained of mucosal Candida colonization or infection by swabbing. Each sample was plated on CHROMagar®Candida and incubated (36 ± 1.5 °C) for two days. The yeast species were identified using the API®ID32-C-AUX. Fluconazole susceptibility was tested using a broth microdilution assay according to the CLSI methods.ResultsThe yeast colonization/infection frequency in the total population was 65.8%. The frequency of the highest Candida carriers was 67.4% in the 70–79-year-old-group. Oral candidiasis was present in 20%, with a tendency to increase with age (33.3% of adults aged > 80 years), it was determined that the use of prosthesis is associated with a higher colonization rate (Chi2, p = 0.011). The frequency of colonization/infection cases with more than one species showed a tendency to increase with age; 18.9% in the 60–69 year-old-group, 20.9% in the 70–79-year-old-group and 29.2% in the ≥80 year-old-group. About fluconazole susceptibility: for C. albicans, 20.3%, about Candida non-albicans species 15.3% were dose dependently susceptible (DDS) and 17.9% were resistant.ConclusionsAfter 80 years of age, there is a considerable increase in Candida non-albicans species and a reduced susceptibility to fluconazole.