Implants are increasingly used to substitute missing structure or functions in the human body. Despite improved design, biocompatibility and functionality, implants also carry a significant risk of infection. Implant-associated infections are one of the most feared and difficult to treat complications, causing high morbidity and considerable mortality as well as consuming substantial health care costs.
Identification of underlying factors and the bacterial species associated with the infections has pointed to the significant and previously underestimated role of skin-colonizing bacteria, such as Propionibacterium acnes and Staphylococcus epidermidis. The background facilitating this type of infections includes heightened virulence of specific strains, appropriate conditions for growth and biofilm formation, which are significantly influenced by the effectiveness of the immune responses generated by the human host.