Experimental Staphylococcus epidermidis implant infection in the mouse. Kinetics of rifampin and vancomycin action

Staphylococcus epidermidis implant infections remain a therapeutic challenge; they frequently result in failure of conservative management and require removal of the implant. This resistance to antibiotic therapy has been ascribed to the presence of a protective bacterial biofilm at the surface of the implant. An animal model of implant associated infection has been developed in which preformed bacterial biofilm catheter segments are implanted intraperitoneally, resulting in a chronic standardized localized infection. The authors have determined the superior rapid action of rifampin (Cieba-Geigy) compared to vancomycin hydrochloride (Eli Lilly) and determined that the combination is superior to either used alone. No rifampin resistant surviving infection was noted, which indicates the significant contribution of mammalian host defenses. This animal model is an excellent vehicle for the study of Staphylococcus epidermidis implant associated infection and the evaluation of the relative efficacy of antibiotic regimens, singly and in combination.