Infection Potentiation Study of Synthetic and Naturally Derived Surgical Mesh in Mice

Abstract

To evaluate the potential of synthetic surgical meshes (Marlex((R)) mesh [C.R. Bard, Inc., Murray Hill, NJ]; MYCROMESH PLUS [W.L. Gore and Associates, Inc., Flagstaff, AZ]; GYNECARE GYNEMESH Nonabsorbable PROLENE* Soft Mesh [Ethicon, Somerville, NJ]; and naturally derived surgical mesh materials (DermMatrix) [Carbon Medical Technologies, St. Paul, MN] and SURGISIS [Cook Surgical, Spencer, IN]) to serve as a nidus for microbial attachment and growth, thus exacerbating surgical site infection. Meshes were implanted subcutaneously in mice and inoculated with 10(4) colony-forming units (cfu) of Staphylococcus aureus. Mice were euthanized four days later, and the implants were removed, homogenized, and cultured using a standard agar pour plate method to determine the number of viable bacteria that could be recovered from each implant. The Marlex mesh and Gynecare Gynemesh PS were comparable and "neutral" to infection, the average number of bacteria recovered being 1.61 x 10(5) and 5.41 x 10(4) cfu, respectively. Mycromesh Plus, with its antibacterial coating, resulted in a reduction in the number of bacteria recovered, the average being 1.61 x 10(1) cfu. Naturally derived meshes were considered to potentiate infection on the basis of macroscopic observation of infection and significantly increased numbers of bacteria recovered from the implant: 1.84 x 10(8) cfu from DermMatrix and 3.17 x 10(7) cfu from Surgisis. The synthetic meshes did not potentiate infection in this model, whereas the naturally-derived materials did. As this preclinical model was able to detect differences between different implant materials, it may have utility in assessing the infection potentiation properties of newly developed materials.