prevalence of candida species in the oral cavity of patients undergoing head and neck radiotherapy

background and aims. candidiasis is a common opportunistic infection in immunocompromised patients. radiation to the head and neck affects the oral mucous membrane and produces xerostomia. xerostomia alters the oral mucosa and predisposes them to colonization by candida species. the aim of this study was evaluation of candida species before and after radiotherapy. materials and methods. twenty patients undergoing radiation therapy were selected. none of the patients had taken any antibiotics and antifungals during the 3-month period prior to the study and did not take any during the study; in addition, they did not have any systemic conditions predisposing them to candida infections. swabs were collected from all the patients for candida species culturing procedures 3±1 days before treatment and 2 and 4 weeks after radiotherapy. swabs were inoculated on 2% sabouraud’s dextrose agar. different types of candida species are specified by colony color. analysis of variance was used to assess the difference between the periods before and after treatment. results. mean age of the patients were 59.4 years. ten patients were candida-positive before the initiation of radiotherapy. eighteen and 20 patients were candida-positive after two and four weeks of radiotherapy, respectively. the most frequent type of candida in this study was candida albicans both before and after radiotherapy. conclusion. the present study suggests that patients undergoing head and neck radiotherapy should take antifungal agents, especially sugar-free agents, topical fluoride and salivary substitutes. the most commonly found candida in this study was candida albicans, which might be attributed to its high pathogenecity.