Background: Oral candidiasis is one of the most prevalent opportunistic fungal infections among immunocompromised cancer patients.

Objective: The aim of this study was to assess the distribution and in vitro antifungal susceptibility patterns of oral Candida species isolated from immunocompromised cancer patients at southern Iraq.

Methodology: This study involved a prospective cross-sectional review of 172 cancer patients receiving chemotherapy while admitted in a medical Centre between June to October 2023. Methods: Oropharyngeal swabs were cultured on Sabouraud Dextrose Agar and Candida Chromogenic Agar. Identification of Candida albicans was established with the germ tube test and antifungal susceptibility testing (AFST). We evaluated susceptibility to fluconazole, voriconazole, caspofungin, micafungin, amphotericin B and flucytosine.

Results: Five species of Candida were detected. The most prevalent isolate was C. albicans at 59.9% followed by C. glabrata (16.9%), C. parapsilosis (12.2%), C. tropicalis (7.6%) plus a total of 3,5% with result for the both latter species group identified as C. krusei. The overall susceptibility rates to amphotericin B, flucytosine, caspofungin, voriconazole, micafungin and fluconazole were 78.5%, 72.7%, 70.9%, 70.3%, 66.9% and a lowest rate of 53.5%. Fluconazole, voriconazole, caspofungin and flucytosine exhibited significantly different susceptibilities according to the species of Candida (all p<0.05). This was most clearly the case for C. glabrata and C. krusei isolates, which had low sensitivity to fluconazole.

Conclusion: C. albicans is the most common species isolated, but a considerable prevalence of non-albicans Candida species with high azole resistance represents a clinical challenge among immunosuppressed cancer patients.