Characterisation and antifungal susceptibilty testing for candida species in a tertiary care hospital

ACKGROUND AND OBJECTIVES: The last two decades have seen a significant rise in the infections caused by Candida species in various centers in India. There are reports of resistance by Candida spp. to antifungal therapy. The objective of this study was to isolate and speciate Candida species from various clinical samples, to detect their antifungal susceptibility pattern and to note down the risk factors. METHODS: Candida species isolated from various clinical samples were subjected to speciation using standard yeast identification protocol and CHROM agar. Antifungal susceptibility testing was done by the disc diffusion method to amphotericin B, fluconazole, nystatin and clotrimazole. Clinical details and risk factors of the patients were noted down. RESULTS: Among the 147 culture positive cases, eight Candida species which were isolated were C. tropicalis (46.25%), C. albicans (29.25%), C. parapsilosis (10.20%), C. glabrata (6.12%), and C. guilliermondii (4.76%), C. stellatoidea (1.36%) and C. kefyr (1.36%) and of C. lusitanae (0.68%). The susceptibility pattern showed that of the 147 isolates, 30.6% were resistant to fluconazole, 28.5% were resistant to clotrimazole and 11.56% were resistant to nystatin. No resistance was seen to amphotericin B. CONCLUSION: Isolation of non-Candida albicans species was more than Candida albicans. Candida tropicalis was the predominant isolate. The risk factors noted in this study were diabetes mellitus, prolonged medication, low birth weight and pregnancy. The antifungal resistance was more in the non-Candida albicans species than in Candida albicans. Hence there is a need for speciation, susceptibility testing and periodic surveillance of Candida species.