Efficacy of clarithromycin plus vancomycin in mice with implant-related infection caused by biofilm-forming Staphylococcus aureus.
BACKGROUND
Staphylococcal biofilms pose an important problem, especially after orthopedic surgery using foreign implants. Clarithromycin (CAM) eliminates the biofilms formed by a wide variety of aerobic and anaerobic bacteria. In a previous in vitro study, we showed that treatment with CAM and vancomycin (VCM) eradicated staphylococcal biofilms from surgical implants. To investigate the efficacy of this eradication therapy, we assessed its effects against Staphylococcus aureus on titanium plates implanted in mice.


METHODS
A titanium washer covered with S. aureus biofilms was implanted in the muscular tissue around the femoral bone. Mice were given intravenous injections of CAM and intraperitoneal injections of VCM twice daily beginning 72 h after implantation. To confirm eradication of biofilms and S. aureus strains, the resected washer was examined by scanning electron microscopy.


RESULTS
Dense colonization and biofilms were seen on the washer implanted in the control mice that received saline, saline plus CAM, or saline plus VCM. Treatment with CAM plus VCM eliminated the biofilms, indicating an S. aureus eradication effect.


CONCLUSIONS
Staphylococcal biofilms have demonstrated resistance to most antibiotics, including VCM. Our in vivo data support the hypothesis that combined treatment using CAM plus VCM may effectively eradicate staphylococcal biofilms in patients with implant-related infection.
Research Division for Development of Anti-infection Agents, Institute of Development Aging and Cancer, Tohoku University, Sendai, Japan.
Shigeru
S
Fujimura
Tetsuro
T
Sato
Toshiaki
T
Kikuchi
Jamal
J
Zaini
Kazunori
K
Gomi
Akira
A
Watanabe
D000818:Animals; D018441:Biofilms / Q000187:drug effects*; D017291:Clarithromycin / Q000008:administration & dosage*; D004359:Drug Therapy, Combination; D005260:Female; D007262:Infusions, Intravenous; D051379:Mice; D016459:Prosthesis-Related Infections / Q000188:drug therapy* / Q000382:microbiology; D013203:Staphylococcal Infections / Q000188:drug therapy*; D013211:Staphylococcus aureus / Q000187:drug effects* / Q000502:physiology; D014025:Titanium; D014640:Vancomycin / Q000008:administration & dosage*
D014640:Vancomycin; D014025:Titanium; D017291:Clarithromycin