[Candida dubliniensis studies and isolation of Candida types in oropharyngeal specimens from oncologic patients]

Fungal opportunistic infections, and in particular those caused by the various Candida species, have gained considerable significance as a cause of morbidity and, often, mortality. Although Candida albicans remains to be the most frequently isolated fungal species as an opportunistic oral pathogen, other yeast species are often identified in immunocompromised patients. C. dubliniensis, the recently described species, has been recovered primarily from oropharyngeal candidasis in Human Immunodeficiency Virus (HIV)-infected patients. C. dubliniensis shares many phenotypic characteristics with, and is phylogenetically closely related to, C. albicans. The aim of the present study was to investigate the colonization rates of fungal species, and especially C. dubliniensis, in the oropharyngeal samples from cancer patients. The oropharyngeal swabs of 543 patients were collected during their visits to oncology clinic in 9 months period, and a total of 209 Candida species have been isolated. Of them, 147 isolates were found to be positive for germ tube and chlamydospore formation, and they were tested for the growth inability at 42 degrees C and 45 degrees C, colony morphology in Staib agar and the intracellular beta-glucosidase activity, in order to identify C. dubliniensis. The results of these tests and carbohydrate assimilation tests by API 20C AUX yeast identification system, yielded that all these 147 (70.3%) isolates were C. albicans. The other isolates were identified as follows; 16 C. parapsilosis (7.6%), 13 C. tropicalis (6.2%), 10 C. glabrata (4.7%), 5 C. guilliermondii (2.3%), 4 C. krusei (1.9%), 3 C. keyfr (1.4%), 3 C. famata (1.4%), 2 S. cerevisiae (0.9%), 2 C. pelliculosa (0.9%), 1 C. utiles (0.4%), 1 C. neoformans (0.4%) and 1 Hansenula polymorpha (0.4%), while no C. dubliniensis was isolated.