Treatment of implant-related methicillin-resistant Staphylococcus aureus osteomyelitis with vancomycin-loaded VK100 silicone cement: An experimental study in rats.

INTRODUCTION

The purpose of this present study is to investigate the efficacy of vancomycin-loaded VK100 silicone cement drug delivery system in the treatment of implant-related methicillin-resistant Staphylococcus aureus (MRSA) osteomyelitis in rats.

MATERIALS AND METHODS

Thirty-six adult (18-20 weeks old) female Sprague-Dawley rats were included in the study. All rats underwent experimental osteomyelitis surgery via injecting 100 µL bacterial suspension of MRSA into the medullary canal. After a 2-week duration for the formation of osteomyelitis model, rats were assigned randomly into four groups: control (C), systemic vancomycin (V), local vancomycin-loaded VK100 silicone cement (vVK100), and systemic vancomycin and local vancomycin-loaded VK100 silicone cement (V+vVK100). The following treatment protocols were administered to each group for 4 weeks. For group C, 0.9% saline solution equivalent to the volume of vancomycin dose (approximately 1 ml/kg) was administered intraperitoneally twice daily (12-h intervals). For group V, 15 mg/kg of vancomycin was administered intraperitoneally twice daily (12-h intervals). For group vVK100, vVK100 polymer was included so that the intramedullary canal of the rats are affected. For group V+vVK100, vVK100 polymer was included so that the intramedullary canal of the rats are affected and 15 mg/kg of vancomycin was administered intraperitoneally twice daily (12-h intervals). After 4 weeks of treatment, clinical, radiologic, microbiologic, and histopathologic evaluations were performed for all groups.

RESULTS

Results of this study revealed that all scores of the evaluation criteria for the treatment groups (groups V, vVK100, and V+vVK100) decreased due to the treatment protocols when compared to group C. These results show the effectiveness of all treatment protocols for the implant-related chronic MRSA osteomyelitis. However, there were no statistical difference between these three protocols.

CONCLUSIONS

vVK100 polymer, as a local antibiotic delivery system, seems to be an effective method for the treatment of implant-related chronic MRSA osteomyelitis.