Phenotypic antibiotic tolerance of Staphylococcus aureus in implant-related infections: relationship with in vitro colonization of artificial surfaces

Antibiotic therapy of deep-seated staphylococcal infections, especially whe n they are associated with foreign implants, such as orthopedic prostheses and permanently inserted catheters, is a difficult challenge. Semi-syntheti c penicillins, glycopeptides and quinolones are found effective when given prophylactically in clinical and experimental trials of implant-related inf ections, but are frequently poorly effective after implant-related infectio ns are established. Thus, removal of the medical devices is often required to obtain cure. The failure of antibiotic therapy to cure staphylococcal fo reign body infections may arise from a broad-spectrum phenotypic tolerance to different classes of antimicrobial agents, whose molecular basis and phy siological mechanisms are poorly understood.