Characterization of fungal biofilm-based catheter-related sepsis

Abstract

Background: Fungi most commonly associated with nosocomial septicemia are in the genus Candida . Attachment of yeasts to intravascular surfaces is the crucial step in initiating colonization by yeast cells, forming biofilms and resulting in disseminated infection depending on various factors. Aims: To study the rate and profile of fungal biofilms in catheter-related sepsis (CRS) and antifungal resistance among the clinical isolates of CRS was the aim of this study. Materials & Methods: In all, 135 hospitalized pediatric patients with peripheral intravascular catheters (IVCs) and clinical suspicion of nosocomial septicemia were studied. The yeast isolates causing CRS were identified and characterized, and antifungal susceptibility testing by microplate alamar blue method (minimum inhibitory concentration) was also done. The fungal biofilm formations were visualized by scanning electron microscopy and tube method. Results: 7.4% patients with IVC had CRS, majority being caused by Candida albicans biofilms. In vitro antifungal susceptibility testing of yeast isolates causing CRS demonstrated moderate to high level of resistance to fluconazole (70%). Voriconazole was the most optimum drug to cure such infections. Conclusion: This study illustrates the need for exploration of biofilm-based CRS (fungemia) in hospitalized patients and to design practical guidelines for their management (diagnosis and treatment).