[Effects of a combination therapy consisting of arbekacin and ampicillin of methicillin-resistant Staphylococcus aureus].
Investigations were made on effects of a combination therapy consisting of arbekacin (ABK) and ampicillin (ABPC) against methicillin-resistant Staphylococcus aureus (MRSA). The following conclusions were drawn. 1. A frequency of FIC index to be < or = 0.5 upon a combination therapy consisting of ABK and ABPC against MRSA was 48.7%, hence this therapy showed better antibacterial effects than the other 8 combination therapies consisting of ABK and other antibiotics previously studied. 2. A combination therapy consisting of ABK and ABPC against MRSA was better than any other combination therapy because ABPC had a higher binding affinity with penicillin-binding protein 3 of MRSA, and because a high antibacterial activity of ABPC was maintained during the combination therapy. ABPC did not lose antibacterial activity largely because MRSA dose not produce beta-lactamase, or most of MRSA produces little beta-lactamase activity. 3. Our data indicate that the success of a combination therapy against MRSA depends upon the effects of the drug under sub MIC concentrations.
Deguchi
K
K
Tokyo Clinical Research Center.
Yokota
N
N
Koguchi
M
M
Suzuki
Y
Y
Suzuki
K
K
Fukayama
S
S
Ishihara
R
R
Oda
S
S
D000617:Aminoglycosides; D000667:Ampicillin / Q000494:pharmacology; D000900:Anti-Bacterial Agents; D003982:Dibekacin / Q000031:analogs & derivatives / Q000494:pharmacology; D004357:Drug Synergism; D004359:Drug Therapy, Combination / Q000494:pharmacology*; D006801:Humans; D016106:Methicillin Resistance; D008826:Microbial Sensitivity Tests; D013211:Staphylococcus aureus / Q000187:drug effects*; D001618:beta-Lactamases / Q000032:analysis
D000617:Aminoglycosides; D000900:Anti-Bacterial Agents; D003982:Dibekacin; D000667:Ampicillin; D001618:beta-Lactamases; C031986:arbekacin