title: Ultrasonically enhanced vancomycin activity against Staphylococcus epidermidis biofilms in vivo.
abstract: Infection of implanted medical devices by Gram-positive organisms such as Staphylococcus ssp. is a serious concern in the biomaterial community. In this research the application of low frequency ultrasound to enhance the activity of vancomycin against implanted Staphylococcus epidermidis biofilms was examined. Polyethylene disks covered with a biofilm of S. epidermidis were implanted subcutaneously in rabbits on both sides of their spine. The rabbits received systemic vancomycin for the duration of the experiment. Following 24 h of recovery, one disk was insonated for 24 or 48 h while the other was a control. Disks were removed and viable bacteria counted. At 24 h of insonation, there was no difference in viable counts between control and insonated biofilms, while at 48 h of insonation there were statistically fewer viable bacteria in the insonated biofilm. The S. epidermidis biofilms responded favorably to combinations of ultrasound and vancomycin, but longer treatment times are required for this Gram-positive organism than was observed previously for a Gram-negative species.
authors.affiliation: Department of Micro and Molecular Biology, Brigham Young University Provo, UT 84602, USA.
authors.forename: J C
authors.initials: JC
authors.lastname: Carmen
authors.forename: B L
authors.initials: BL
authors.lastname: Roeder
authors.forename: J L
authors.initials: JL
authors.lastname: Nelson
authors.forename: B L
authors.initials: BL
authors.lastname: Beckstead
authors.forename: C M
authors.initials: CM
authors.lastname: Runyan
authors.forename: G B
authors.initials: GB
authors.lastname: Schaalje
authors.forename: R A
authors.initials: RA
authors.lastname: Robison
authors.forename: W G
authors.initials: WG
authors.lastname: Pitt
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage; D018441:Biofilms / Q000187:drug effects* / Q000528:radiation effects*; D002470:Cell Survival / Q000187:drug effects* / Q000528:radiation effects*; D003131:Combined Modality Therapy; D004305:Dose-Response Relationship, Drug; D004307:Dose-Response Relationship, Radiation; D005260:Female; D016459:Prosthesis-Related Infections / Q000188:drug therapy / Q000532:radiotherapy; D011817:Rabbits; D013203:Staphylococcal Infections / Q000188:drug therapy / Q000532:radiotherapy; D013212:Staphylococcus epidermidis / Q000187:drug effects* / Q000528:radiation effects*; D014464:Ultrasonic Therapy / Q000379:methods; D014465:Ultrasonics; D014640:Vancomycin / Q000008:administration & dosage*
chemical_list: D000900:Anti-Bacterial Agents; D014640:Vancomycin