Morphological aspects of surgical meshes as a risk factor for bacterial colonization.

BACKGROUND: Prosthetic meshes are increasingly popular in abdominal wall reconstructive surgery owing to a reduction in hernia recurrence rate. Individual meshes have been evaluated with respect to the formation of infectious biofilms, but no comprehensive comparison yet exists. The aim of this study was to evaluate the effect of the material and morphology of surgical meshes on biofilm growth. METHODS: Biofilms of a coagulase-negative staphylococcus, Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa were grown in vitro on different meshes. Intact biofilms were stained fluorescently and evaluated with confocal laser scanning microscopy to distinguish dead from live bacteria and slime. RESULTS: Numbers of adhering bacteria and the amount of slime in the biofilm were dependent on the morphology of the mesh. Hydrophobicity and the presence of niches in multifilament meshes contributed most to increased biofilm growth. CONCLUSION: The morphological properties of surgical meshes as well as their hydrophobicity influence bacterial growth and slime production. Differences in slime production may explain why the effectiveness of antibiotic treatment varies for different types of mesh