Efficacy of daptomycin combined with rifampicin for the treatment of experimental meticillin-resistant (MRSA) acute osteomyelitis

International audienceDaptomycin exhibits rapid bactericidal activity against Gram-positive organisms, including meticillin-resistant (MRSA). Daptomycin in combination with rifampicin needs to be assessed in bone infection. An MRSA acute osteomyelitis model was used. Daptomycin and vancomycin were compared, alone or in combination with rifampicin, over 4 days. Surviving bacteria were counted in bone, bone marrow and joint fluid. Vancomycin and daptomycin as single therapies were ineffective, but both combinations were significantly more effective than the corresponding monotherapy. Combination of daptomycin and rifampicin could prevent from developing resistance. This combination could be a useful alternative to treat MRSA osteomyelitis at an early stage