Oral candidiasis identification and profile of Candida in Brazilian patients undergoing radiotherapy in the head and neck region and in patients with removable complete dentures

Abstract

Introduction: Candidiasis is the most common oral fungal infection in humans affecting mainly people who are debilitated or immunocompromised patients, such as those irradiated for head and neck cancer. Pourpose: Identifing Candida species in head and neck irradiated patients and in those with total removable dental prosthesis by three microbiological methods. Material and Methods: Samples were collected with disposable sterile swabs of twenty-seven patients through exfoliative cytology. The Sabouraud media containing the inoculum were left in an aerobic environment at 36oC during 24 hours. Thus, yeasts were taken to the Laboratory of Taxonomy, Biodiversity and Biotechnology of Fungi to have the respective test for Candida identification with Candifast®, CHROMagar® and PCR EI1®. Results: The pseudomembranous clinical candidosis was more prevalent in Group 1, while the denture stomatitis was the most frequent clinical form in Group 2. There were differences in identification when comparing the three methods. On the other hand, PCR was faster and more effective when compared with CHROMagar, followed by Candifast®. PCR (EI1 and NLI/NL4) identified in Group 1 as C. albicans (37.1%), C. tropicalis (55%), (7.4%) C. krusei. In Group 2 PCR allowed the identification of 68% C. albicans, 20% as C. tropicalis, 8% as C. glabrata and 4% C. parapsilosis. Conclusion: The Candifast® Kit was found to be defective in the identification of several species of Candida, as compared to the molecular identification method used (PCR EI1 and PCR NL1 / NL4). CHROMagar® Candida medium was a good method for the presumptive identification of Candida species.

DOI:https://doi.org/10.56238/sevened2023.004-031