Antimicrobial effect of biological surgical mesh added with vancomycin or silver nanoparticles for multidrug-resistant bacteria: experimental study in rats.

Abstract

<h4>Introduction</h4>Surgical site infection (SSI) and polypropylene mesh (PPM) infections are recurrent problems in abdominal hernia surgeries, highlighting the need for a new antimicrobial material for surgical repair. The aim of this study was to evaluate the in vivo antimicrobial effect of a new biological mesh made of decellularized bovine pericardium (BP), added with vancomycin (VAN) or silver nanoparticles (AgNPs), as prevention for SSI.<h4>Methods</h4>Thirty-five Wistar rats were divided into four groups: BP C+ (n=9) with BP without additions; PP C+ (n=8) with PPM; BP AgNPs (n=9) with BP added with silver nanoparticles; and BP VAN (n=9) with BP added with vancomycin. The 1 cm² meshes were stitched into the muscle fascia under the subcutaneous tissue of the rats' backs, followed by inoculation with methicillin-resistant Staphylococcus aureus. The animals were observed for 7 days, with subsequent euthanasia, and histological and bacteriological analysis.<h4>Results</h4>The BP VAN group had better infection control compared to the PP C+ and BP AgNPs groups (1x10¹ vs. 1.4x10³CFU/g, p=0.0303; 1x10¹ vs. 1.5x104CFU/g, p<0.0001, respectively). BP AgNPs showed less bacterial reduction compared to BP C+ (p=0.042). In the histological analysis, there was a mild inflammatory reaction in BP VAN, moderate in BP C+, and intense in PP C+ and BP AgNPs.<h4>Conclusion</h4>BP added with vancomycin showed promising antimicrobial action, while the use of silver nanoparticles did not demonstrate efficacy in this study.