title: Piperacillin (T-1220), a new semisynthetic penicillin. II. In vitro antimicrobial activity and synergy comparison with carbenicillin and gentamicin.
abstract: Piperacillin, a new semisynthetic penicillin, was found to have potent antimicrobial activity against nearly all (405) tested bacterial species. Piperacillin was consistently 4 approximately 16-fold more active than carbenicillin against the Enterobacteriaceae, 16 approximately 32-fold against Pseudomonas aeruginosa and Pseudomonas species, and 16-fold against Streptococcus faecalis. Carbenicillin and piperacillin were equally effective against Staphylococcus aureus, but inactivated by beta-lactamase. A 38% overall synergy rate for the piperacillin-gentamicin combination was identified, a finding similar to that for carbenicillin-gentamicin. Highest incidences of synergy were found for both antibiotic pairs tested on gentamicin-resistant isolates (Ps. aeruginosa and Providencia). In vitro findings suggest that piperacillin alone or in combination with aminoglycosides may be highly efficacious in the treatment of most serious bacterial infections.
mesh_terms: D001419:Bacteria / Q000187:drug effects*; D002228:Carbenicillin / Q000494:pharmacology*; D004357:Drug Synergism; D005839:Gentamicins / Q000494:pharmacology*; D008712:Methicillin / Q000494:pharmacology; D008826:Microbial Sensitivity Tests; D010406:Penicillins / Q000494:pharmacology*; D013997:Time Factors
chemical_list: D005839:Gentamicins; D010406:Penicillins; D002228:Carbenicillin; D008712:Methicillin