Isolation of Candida dubliniensis in Patients with Denture Stomatitis

Although Candida albicans is the most prevalent yeast species associated with denture stomatitis, a number of other species have been isolated. In 1995 the new species Candida dubliniensis, which phenotypically resembles C. albicans, was identified. This species is generally regarded as an upcoming opportunistic pathogen and there is a need to know more about its pathogenicity and epidemiology. Since it's identification, only one reference of the isolation of this species in a denture stomatitis patient had been made. Objectives: The purpose of this study was to investigate the involvement of C. dubliniensisin patients with yeast associated denture stomatitis. Methods: Twenty edentulous patients wearing full dentures and with clinical signs of denture stomatitis were asked to perform an oral rinse with phosphate buffered saline after removal of their dentures. A 0.1 ml aliquot was plated on Sabaroud Dextrose Agar medium for a total yeast count and on Pal's agar for yeast differentiation and isolation of Candida species. After aerobic incubation at 37° C representative colonies were isolated and each individually identified to species level. The tests used were: germ tube formation, growth at 45°C, b-glucosidase activity, colony morphology on Pal's agar and the API 20 C auxanogramme kit. Results: Twenty-five yeasts were isolated of which 14 (56 %) were identified as C. albicans, 5 (20%) as Candida glabrata, 4 (16 %) as C. dubliniensis and 2 (8%) as Candida tropicalis. Conclusion: From these results it appears that C. dubliniensis may be involved in candida associated denture stomatitis but at a relatively low frequency compared to that of C. albicans.