The in vitro activity of sulbactam combined with third generation cephalosporins against third generation cephalosporin-resistant bacteria.
The in vitro activity of the beta-lactamase inhibitor sulbactam combined with cefuroxime, cefotaxime or ceftazidime in the ratio of 1:1 was studied against ceftazidime- or cefuroxime-resistant Gram-negative rods and Staphylococcus aureus. Sulbactam enhanced the antibacterial activities of cefuroxime, cefotaxime and ceftazidime against Gram-negative rods. The MIC(90) of ceftazidime against Escherichia coli, Enterobacter cloacae, Citrobacter freundii, Acinetobacter spp. and Pseudomonas aeruginosa was reduced 4-fold and that of cefotaxime against E. coli, E. cloacae, C. freundii and Acinetobacter spp. reduced by 2-4-fold. However, sulbactam did not enhance the activities of cefuroxime, cefotaxime or ceftazidime against S. aureus, enterococci and Stenotrophomonas maltophilia. With the combination of sulbactam and ceftazidime at the ratio of 1:1, 38.4% of E. coli, 45.3% of E. cloacae, 66.6% of C. freundii and 60% of Acinetobacter spp. initially resistant to ceftazidime became susceptible.
Zhang
Y L
YL
Institute of Clinical Pharmacology, The First Hospital, Beijing Medical University, 100083, Beijing, People's Republic of China. zhengyl@163bj.com
Li
J T
JT
D018550:Cephalosporin Resistance; D002511:Cephalosporins / Q000494:pharmacology*; D004359:Drug Therapy, Combination / Q000494:pharmacology*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006090:Gram-Negative Bacteria / Q000187:drug effects*; D006094:Gram-Positive Bacteria / Q000187:drug effects*; D008826:Microbial Sensitivity Tests; D013407:Sulbactam / Q000494:pharmacology*; D065093:beta-Lactamase Inhibitors
D002511:Cephalosporins; D004791:Enzyme Inhibitors; D065093:beta-Lactamase Inhibitors; D013407:Sulbactam