Prevalence of virulence factors and antifungal susceptibility testing of Candida species isolated from clinical specimens

Abstract

Introduction: The main aim of our study is to isolate and identify Candida species from clinical samples and to detect the virulence markers and also to determine their susceptibilities to various antifungal agents. Materials and Methods: Eighty Candida isolates from respiratory samples were included in the study. Detection of various virulence markers of candida spp such as Phospholipase, Proteinase, Hemolysin and Biofilm production was carried out by Phenotypic methods. Antifungal susceptibility testing of the isolated yeasts for Amphotericin B, Itraconazole, Fluconazole, Caspofungin and Voriconazole was determined by E-test methods. Results: In our study, most common spp isolated was Candida albicans(65%) followed by Candida tropicalis(15%) and Candida glabrata(10%).Prevalence percentage of virulence factors such as Hemolysin, Proteinase, Biofilm and Phospholipase production in Candida spp were 85%, 77.5%, 68.8% and 45% respectively. The susceptibility pattern of Candida isolates to antifungal agents showed highest resistant rate of 33.8% for Itraconazole and lowest resistant rate of 2.5% for Caspofungin. Conclusion: Presence of virulence factors in Candida species might indicate invasiveness and its relation with infection. Hence the significance of virulence determination and antifungal susceptibility testing should be adopted as a routine procedure in the laboratory. Keywords: Candida species, E-test, Hemolysin Biofilm formation, Proteinase, phospholipase activity.