Results of a study of the activity of antibiotic lock solutions of vancomycin and telavancin against biofilm-forming strains of Staphylococcus epidermidis, Enterococcus faecalis, and Staphylococcus aureus are reported.Methods
An established in vitro central venous catheter model was used to evaluate lock solutions containing vancomycin (5 mg/mL) or telavancin (5 mg/mL), with and without preservative-containing heparin sodium (with 0.45% benzyl alcohol) 2500 units/mL, heparin, and 0.9% sodium chloride solution. Lock solutions were introduced after 24-hour bacterial growth in catheters incubated at 35 °C. After 72 hours of exposure to the lock solutions, catheters were drained, flushed, and cut into segments for quantification of colony-forming units.Results
Against S. epidermidis, vancomycin and telavancin (with or without heparin) had similar activity. Against E. faecalis, vancomycin alone was more active than telavancin alone (p < 0.01). Against S. aureus, vancomycin plus heparin had activity similar to that of vancomycin alone; both lock agents had greater activity than telavancin (p < 0.02). The addition of heparin was associated with reduced activity of the vancomycin lock solution against S. epidermidis and E. faecalis (p < 0.01). Telavancin activity was not significantly changed with the addition of heparin.Conclusion
In a central venous catheter model, vancomycin and telavancin activity was similar in reducing biofilm-producing S. epidermidis. However, vancomycin was more active than telavancin against E. faecalis and S. aureus. None of the tested agents eradicated biofilm-forming strains. The addition of preservative-containing heparin sodium 2500 units/mL to vancomycin was associated with reduced activity against S. epidermidis and E. faecalis.