Fusidic acid alone or in combination with vancomycin for therapy of experimental endocarditis due to methicillin-resistant Staphylococcus aureus.
The usefulness of fusidic acid, alone or combined with vancomycin, was investigated for the therapy of experimental endocarditis caused in rabbits by a methicillin-resistant strain of Staphylococcus aureus. In vitro killing curves showed an indifferent interaction between the two antibiotics. In vivo, vancomycin alone was as effective as a vancomycin-fusidic acid combination (P < 0.05 versus control animals). No resistance to fusidic acid emerged during combination therapy. Fusidic acid alone was not effective. Resistance emerged in 5 of 12 animals treated with fusidic acid alone and was responsible for antibacterial failure. Fusidic acid alone was effective (P < 0.001) and did not select resistant strains if therapy was started when animals retained a smaller inoculum. We concluded that the vancomycin-fusidic acid combination exhibited no advantage over vancomycin alone in this model.
Fantin
B
B
Institut National de la Santé et de la Recherche Médicale, Unité 13, Service de Médecine Interne, Hôpital Bichat, Paris, France.
Leclercq
R
R
Duval
J
J
Carbon
C
C
D000818:Animals; D004352:Drug Resistance, Microbial; D004359:Drug Therapy, Combination; D004697:Endocarditis, Bacterial / Q000188:drug therapy* / Q000382:microbiology; D005672:Fusidic Acid / Q000493:pharmacokinetics / Q000627:therapeutic use*; D006801:Humans; D016106:Methicillin Resistance; D011817:Rabbits; D013203:Staphylococcal Infections / Q000188:drug therapy* / Q000382:microbiology; D013211:Staphylococcus aureus / Q000187:drug effects; D014640:Vancomycin / Q000627:therapeutic use*
D005672:Fusidic Acid; D014640:Vancomycin