C1-190. Prevention of S. aureus Biofilm In Vitro Using 5-FU-Coated Central Venous Catheters
Session: Poster Session: Staphylococcus aureus: MRSA and More
Saturday, October 25, 2008: 12:00 AM
Room: Hall C
Background: Biofilm growth on central venous catheters (CVC) is established as an important factor in blood stream infections. This study evaluated a novel 5-Fluorouracil-coated CVC (5-FU) for preventing biofilm formation. Methods: CVC segments were inoculated with Staphylococcus aureus and incubated at 37 °C in a once-through flow system perfused with an iron-limited serum-supplemented medium for 24-96 hours. Biofilms were removed from the segments, dispersed to produce a suspension and enumerated using the spread plate technique. Confocal scanning laser microscopy (CSLM) was used to image biofilms on the segments. Test segments included uncoated polyurethane catheters (UC), coated polyurethane catheters with 5-FU (5-FU), and Arrowgard Blue® catheters (CHSS), which contain chlorhexidine and silver sulfadiazine.
Results: Geometric mean (GM) biofilm populations on UC were 3.8 x 102 CFU/cm2 after 24h and increased to 1.9 x 104 and 7.0 x 105 CFU/cm2 by 48h and 72h, respectively. Biofilm populations at 96h were similar to 72h with a GM of 1.5 x 105 CFU/cm2. Log differences (LD) were calculated from UC within the same experiment at each time point; the mean LD was calculated from repeat experiments. For 5-FU, the mean LD increased from 1.3 after 24h to 2.7 after 48h, to 4.4 after 72h, to 5.4 after 96h. The mean LD for CHSS was 3.6 after 48h, 2.0 after 72h, and 4.2 after 96h. CSLM imaging of the catheters was complicated by binding or reaction of the fluorescent stains, especially with the CHSS catheter coatings. Calcein AM (CAM) proved an effective stain for imaging S. aureus biofilms on the surface of 5-FU-coated catheters. CSLM of CAM-stained 5-FU revealed considerably less biofilm than U, in agreement with the plate count results. Conclusions: (1) Significantly less biofilm accumulated on 5-FU-coated CVC than on uncoated CVC. (2) Less biofilm accumulated on CHSS than 5-FU after 48h, but the opposite trend was observed after 72 and 96h.
Garth James, PhD, Scott Rosebrough, PhD, Angiotech Pharmaceuticals, Inc., Henrietta, NY, Steve Fisher, Montana State University and  G. A. James,
Angiotech Pharmaceuticals, Inc. Role(s): Research Contractor, Received: Research Support.