Infection of prosthetic grafts, especially with methicillin-resistant Staphylococcus aureus (MRSA), often becomes critical. Although
topical administration of
antibiotics has been applied empirically, no comprehensive data are available showing long-lasting effects and safety of local
antibiotic usage. By means of animal experiments we assessed
fibrin glue (FG) as a slow-release vehicle for
vancomycin (VCM) against local MRSA
infection. Preliminary in-vitro experiments were performed to confirm that the FG-VCM mixture maintained viscosity as a sealant and led to slow-release of VCM. We next created a subcutaneous pocket in a rodent back and implanted a 1 cm (2) woven graft with 1 ml FG alone, or with serial concentrations of VCM (0-120 mg/ml. n = 3 for each group). MRSA of 1 × 10(7) colony-forming units (CFU) was injected into the pocket after
wound closure. The graft was explanted 7 days later and was submitted for culture ("Culture-graft"). Blood samples were obtained for regular blood work, serum VCM concentration measurements, and blood culture ("Culture-blood"). The pocket tissue was also submitted for measurement of local VCM concentration. There was a remarkable infectious response in the group without
vancomycin; however, no other groups developed any sign of
infection. "Culture-graft" resulted in MRSA growth for V0 only. "Culture-blood" was negative in all groups, and only minimal serum concentrations of
vancomycin were detected. One-dose
topical administration of VCM via FG was effective against localized MRSA graft
infection without systemic VCM administration.
Topical administration of
antibiotics may help treat difficult graft
infections and reduce systemic use of potent
antibiotics.