Virulence Determinants of Candida Infections in High Risk Neonates and Infants in a Tertiary Hospital of North India

Abstract

Introduction: Candida spp. are considered as opportunistic pathogens because they posses many virulence factors which contributes in the pathogenesis of Candida infections. The virulence of Candida spp. is attributed to certain factors like biofilm formation, and the production of hydrolytic enzymes. Objective: To study the virulence factors of Candida infections among high risk neonates and infants. Materials and methods: Samples were collected aseptically from 128 high risk neonates and infants.They were cultured and identified by standard microbiological techniques and their virulence factors such as biofilm formation was demonstrated by tube method, egg yolk agar for proteinase activity, bovine serum albumin agar for phospholipase activity and sabouraud dextrose agar with sheep blood for haemolytic activity. Results: All the virulence markers were significantly associated with the development of candidiasis among neonates and infants. However among all these factors biofilm and hemolysin production were found to be highly significant. Biofilm formation in this study was more often found in the non albicans Candida spp. (95%) as compared to Candida albicans. C. tropicalis produces stronger biofilms (40% were 3+ & 10% were 4+) than C. albicans (10.3% produced 3+ and 4+ biofilms). Phospholipase activity was noted in 34.7% of Candida spp., Maximum phospholipase production was seen in NAC spp. (65%) as compared to C. albicans (13.6%). Proteinase activity was seen 38.8% of Candida isolates. Conclusion: As non-albicans Candida infections are on the rise, microbiology laboratories should go for complete identification of all yeast isolates and their virulence.