Synergy of sulbactam and ampicillin against methicillin-resistant staphylococci.
Methicillin resistance in staphylococci is an increasing problem both for Staphylococcus aureus (MRSA) and Staphylococcus epidermidis (MRSE), which cause infections of the heart and after central nervous system surgery. Resistance seems to be due primarily to production of altered penicillin-binding proteins. The present study determined whether a combination of beta-lactamase inhibitor sulbactam and ampicillin or sulbactam and cefazolin would inhibit MRSA and MRSE. Sulbactam, ampicillin and cefazolin at 32 micrograms/ml did not inhibit MRSA or MRSE. At 8 micrograms/ml of each agent all isolates were inhibited. Synergy of sulbactam and ampicillin could be demonstrated against MRSA by the agar fixed ratio method, checkerboard dilution and by killing curves. This suggests that in certain situations MRSA and MRSE may be effectively eliminated by this method.
D000667:Ampicillin / Q000494:pharmacology*; D001426:Bacterial Proteins; D002352:Carrier Proteins / Q000096:biosynthesis; D002437:Cefazolin / Q000494:pharmacology; D004357:Drug Synergism; D006602:Hexosyltransferases; D008712:Methicillin / Q000494:pharmacology*; D002267:Muramoylpentapeptide Carboxypeptidase / Q000096:biosynthesis; D010397:Penicillanic Acid / Q000494:pharmacology*; D010403:Penicillin Resistance; D046915:Penicillin-Binding Proteins; D010458:Peptidyl Transferases; D013210:Staphylococcus / Q000187:drug effects*; D013407:Sulbactam
D001426:Bacterial Proteins; D002352:Carrier Proteins; D046915:Penicillin-Binding Proteins; D000667:Ampicillin; D010397:Penicillanic Acid; D010458:Peptidyl Transferases; D006602:Hexosyltransferases; D002267:Muramoylpentapeptide Carboxypeptidase; D002437:Cefazolin; D008712:Methicillin; D013407:Sulbactam