ROLE OF ANTIMICROBIAL-IMPREGNATED POLYMER AND TEFLON IN THE PREVENTION OF BILIARY STENT BLOCKAGE

Biliary stent blockage and microbial colonization is a common complica tion associated with polyurethane stents used for the relief of bile-d uct obstruction caused by benign or malignant disease. in an attempt t o overcome this problem the application of a 'Teflon' (polytetrafluoro ethylene) stent and an antimicrobial benzalkonium chloride (BZC) impre gnated polymer were investigated. The effects of these materials on mi crobial colonization were compared to a polyurethane stent in vitro in broth or bile. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of BZC for three commonly isolated b iliary stent pathogens, Straphylococcus epidermidis, Enterococcus faec ium and Enterobacter cloacae were also determined. All the isolates we re sensitive to BZC. The growth kinetics of the three organisms in bro th and in human pooled bile were similar. Adherence to the BZC impregn ated polymer was significantly reduced as compared to the polyurethane and Teflon stents (P<0.05) in nutrient broth. In bile, fewer organism s attached to the Teflon as compared with the polyurethane stent (P<0. 05) for all organisms. For two of the three test organisms there was l ess bacterial adherence to the Teflon than to the BZC impregnated poly mer. The Teflon and antimicrobial stent materials studied may prevent biliary stent blockage resulting from microbial colonization.