Activity of Different Antistaphylococcal Therapies, Alone or Combined, in a Rat Model of Methicillin-Resistant Staphylococcus epidermidis Osteitis without Implant.
We developed a rat model of methicillin-resistant Staphylococcus epidermidis (MRSE) osteitis without implant to compare the efficacy of vancomycin, linezolid, daptomycin, ceftaroline, and rifampin either alone or in association with rifampin. A clinical strain of MRSE was inoculated into the proximal tibia. Following a 1-week infection period, rats received either no treatment or 3, 7, or 14 days of human-equivalent antibiotic regimen. Quantitative bone cultures were performed throughout the 14-day period. The mean ± SD quantity of staphylococci in the bone after a 1-week infection period was 4.5 ± 1.0 log10 CFU/g bone, with this bacterial load remaining stable after 3 weeks of infection (4.9 ± 1.4 log10 CFU/g bone). Vancomycin monotherapy was the most slowly bactericidal treatment, whereas ceftaroline monotherapy was the most rapidly bactericidal treatment. The addition of rifampin significantly increased the bacterial reduction for vancomycin, linezolid, and daptomycin. All tibias were sterilized after 2 weeks of treatment except for animals receiving vancomycin or daptomycin alone (66.6% and 50% of sterilization, respectively). These results show that ceftaroline and linezolid alone remain good options in the treatment of MRSE osteitis without implant. The combination with rifampin increases the antibiotic effect of vancomycin and daptomycin lines.
['Albac|S|S|', 'Labrousse|D|D|', 'Hayez|D|D|', 'Anzala|N|N|', 'Bonnot|D|D|', 'Chavanet|P|P|', 'Aslangul|E|E|', 'Croisier|D|D|0000-0002-8744-5832']
D000818:Animals D000900:Anti-Bacterial Agents D002511:Cephalosporins D017576:Daptomycin D004195:Disease Models, Animal D006801:Humans D000069349:Linezolid D008297:Male D008712:Methicillin D016106:Methicillin Resistance D055624:Methicillin-Resistant Staphylococcus aureus D010000:Osteitis D051381:Rats D017208:Rats, Wistar D012293:Rifampin D013203:Staphylococcal Infections D013212:Staphylococcus epidermidis D013977:Tibia D014640:Vancomycin
osteitis MRSE preclinical drug studies rifampin combination