title: Activity of beta-lactamase inhibitors in combination with new beta-lactam antibiotics against resistant gram-negative organisms.
abstract: Thirty-eight isolates of gram-negative bacilli resistant to four new beta-lactam antibiotics, aztreonam, moxalactam, ceftazidime, and cefoperazone, were tested in the presence of two beta-lactam inhibitors, clavulanic acid and sulbactam. Microorganisms tested included 22 isolates of Pseudomonas species, 5 of Klebsiella species, and 11 of Enterobacter species. A 2- to 10-fold decrease in minimum inhibitory concentration was noted when antibiotics and beta-lactamase inhibitors were combined compared to antibiotics alone. Four strains of Pseudomonas aeruginosa showed increased resistance to the combination of antibiotics and beta-lactamase inhibitors.
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D019818:Clavulanic Acid; D002969:Clavulanic Acids / Q000494:pharmacology*; D004352:Drug Resistance, Microbial; D004754:Enterobacter / Q000187:drug effects; D006090:Gram-Negative Bacteria / Q000187:drug effects*; D006801:Humans; D007709:Klebsiella / Q000187:drug effects; D008826:Microbial Sensitivity Tests; D010397:Penicillanic Acid / Q000494:pharmacology*; D011549:Pseudomonas / Q000187:drug effects; D013407:Sulbactam; D065093:beta-Lactamase Inhibitors
chemical_list: D000900:Anti-Bacterial Agents; D002969:Clavulanic Acids; D065093:beta-Lactamase Inhibitors; D019818:Clavulanic Acid; D010397:Penicillanic Acid; D013407:Sulbactam