In vivo evaluation of bacterial infection involving morphologically different surgical meshes

OBJECTIVE: To study the influence of morphology of surgical meshes on the course of bacterial infection under the influence of the host immune system in an in vivo chronic bacterial infection model. BACKGROUND: The use of prosthetic meshes has increased dramatically the last decades in abdominal wall reconstructive surgery. Whereas infection is becoming a more frequent complication, attention is increasingly drawn to the influence of the surgeon's mesh choice on the course of this complication. METHODS: Samples of 6 often applied surgical meshes were contaminated with a bioluminescent strain of Staphylococcus aureus and implanted subcutaneously in an immunocompetent BALB/c mouse. The intensity and the spreading of bioluminescence (ie, p/s/cm/sr) were analyzed non-invasively in vivo during a 10-day follow-up period. RESULTS: Over the course of infection, multifilament polypropylene and hydrophobic materials showed a significantly higher persistence of bacteria as well as spreading of infection compared to all other meshes. In contrast, infection resolved in almost all animals with a low-weight polyester mesh. CONCLUSION: The results of this study are in accordance with circumstantial evidence from limited clinical reports on infection involving surgical meshes and suggest that multifilament and hydrophobic meshes significantly increase bacterial persistence or spreading in the infected area in contrast to monofilament polypropylene and lightweight meshes. Therefore, the surgeon should consider this outcome when choosing a mesh graft for limiting infection in abdominal wall repair.