Antibiotic regimens with rifampicin for treatment of Enterococcus faecium in biofilms.

Enterococcus faecium is an important pathogen that is resistant to many antibiotics and is able to form biofilms on implanted medical devices. In this study, the efficacy of rifampicin-containing antibiotic regimens against biofilms of E. faecium in vitro was investigated by determination of the minimum biofilm eradication concentration and by time-kill experiments of bacteria in biofilms formed on beads of bone cement. Rifampicin combined with tigecycline, daptomycin or linezolid was more efficient in reducing bacterial numbers and halting the development of rifampicin resistance than the combination of rifampicin and vancomycin.