1. Activity of Different Antistaphylococcal Therapies, Alone or Combined, in a Rat Model of Methicillin-Resistant Staphylococcus epidermidis Osteitis without Implant
- Author
-
Pascal Chavanet, Sandrine Albac, E Aslangul, Delphine Croisier, N. Anzala, Davy Hayez, D. Bonnot, and Delphine Labrousse
- Subjects
Male ,Gastroenterology ,chemistry.chemical_compound ,Methicillin ,0302 clinical medicine ,Staphylococcus epidermidis ,polycyclic compounds ,Pharmacology (medical) ,030212 general & internal medicine ,Osteitis ,0303 health sciences ,biology ,Methicillin-resistant Staphylococcus epidermidis ,Staphylococcal Infections ,Anti-Bacterial Agents ,Infectious Diseases ,Vancomycin ,Rifampin ,medicine.drug ,Methicillin-Resistant Staphylococcus aureus ,medicine.medical_specialty ,Rat model ,03 medical and health sciences ,Daptomycin ,Internal medicine ,medicine ,Animals ,Humans ,Experimental Therapeutics ,Rats, Wistar ,Pharmacology ,Tibia ,030306 microbiology ,business.industry ,Linezolid ,biochemical phenomena, metabolism, and nutrition ,biology.organism_classification ,medicine.disease ,Cephalosporins ,Rats ,Disease Models, Animal ,chemistry ,Methicillin Resistance ,Implant ,business - Abstract
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 log(10) CFU/g bone, with this bacterial load remaining stable after 3 weeks of infection (4.9 ± 1.4 log(10) 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.
- Published
- 2020