[Evaluation of mixed biofilm formation between Candida albicans and a variety of bacterial species isolated from peripheral catheters at Tlemcen CHU. First study in Algeria]

Abstract

Introduction: Mixed-species biofilms constitute a reservoir of infection for a group of bacteria and yeasts that coexist on the same support. Peripheral venous catheters make up a good surface for the attachment of microorganisms that promote biofilm formation and this requires complex strategies for antimicrobial treatments.

Objective: No such studies on formation mixed biofilms have ever been conducted in Algeria. Therefore, we evaluated the potential for the formation of mixed-species biofilms by Candida albicans and some bacterial species isolated from peripheral vascular catheters at the University Hospital of Tlemcen, in Algeria.

Results: The results obtained showed that C. albicans have the potential to form mixed biofilms with three bacteria (Enterobacter cloacae, Bordetella spp. and Serratia liquefaciens) isolated from the same catheter as the yeasts. The amount of biofilms produced varies depending on the species and the composition of the growth medium. Observations by scanning electron microscopy showed that the structure of the mixed biofilm depends on the surface support the biofilm was formed on, and varies with the species.

Conclusion: A competition was noted between bacteria and yeasts; it depends on the composition of the medium and its pH, which both play an important role in promoting the dominance of one over the other.

Keywords: Bacteria; Bactéries; Biofilm mixte; Candida albicans; Cathéters vasculaires périphériques; Mixed biofilm; Peripheral vascular catheters.