Evaluation of Species Distribution and Antifungal Susceptibility of Candida Species Isolated from Blood Culture

Introduction: Today, the increase in malignancy, chemotherapy, immunosuppressive treatments, and prolonged hospitalization in intensive care units have caused an increase in the incidence of candidemia. Although Candida albicans is the most common cause of candidemia, recent studies have shown an increased frequency of isolation in non-C. albicans species. In addition, resistance to anti -fungal drugs used in treatment has started to emerge. Consequently, it is important to identify the yeast type and assess antifungal susceptibility when selecting appropriate treatment. This study aims to determine the distribution of Candida species and their susceptibility to antifungal agents in Candida spp. isolated from blood cultures.Materials and Methods: Identification of 110 Candida isolated from blood cultures sent to Mersin University Hospital Medical Microbiology Laboratory between 01.01.2020 and 31.12.2020 was performed by using classical methods and VITEK 2 YST yeast identification panels (bioMerieux, France). Antifungal (amphotericin B, fluconazole, voriconazole, itraconazole, micafungin, and anidulafungin) susceptibilities of the isolates were studied by using the EUCAST reference broth microdilution method.Results: The strains included in the study were isolated from blood cultures of 39 (35.5%) female and 71 (64.5%) male patients. The most frequently isolated species from the blood cultures in the study was C. parapsilosis 48 (43.6%), followed by C. albicans 29 (26.3%), C. tropicalis 16 (14.5%), C. glabrata 15 (13.6%) and C. krusei 2 (1.8%). Resistance rates for C. parapsilosis were determined as follows: fluconazole 16.6%, voriconazole 8.3%, anidulafungin 8.3%, amphotericin B 4.3%, micafungin 6.2%, and itraconazole 6.2%. For C. albicans, the resistance rates were as follows: amphotericin B 10.4%, fluconazole 3.5%, voriconazole 3.4%, itraconazole 3.4%, micafungin 3.4%, and anidulafungin 3.4%. As for C. tropicalis, the resistance rates observed were as follows: fluconazole 25%, amphotericin B 18.8%, itraconazole 18.8%, and anidulafungin 6.3%. Lastly, for C. glabrata, the resistance rates were as follows: amphotericin B 18.8% and fluconazole 6.7%. There was no resistance to voriconazole among C. tropicalis isolates, and no resistance to micafungin and anidulafungin among C. glabrata isolates.Conclusion: C. parapsilosis has been identified as the most commonly isolated species in cases of candidemia, and our study has shown a higher resistance rate to fluconazole compared to other antifungal agents. The findings suggest that identifying the specific species in Candida infections and assessing their antifungal susceptibility could be advantageous in terms of treatment effectiveness and pre- vention of resistance development.