Effect of Different Proportions of Cefoperazone/sulbactam against Gram-negative Bacteria in Vitro

ZHANG Ying; AN Cui-ping; NIE Bing; LIANG Guo-rui; LIU Jun-xia

doi:10.3969/j.issn.1002-3429.2015.12.035

Abstract：Objective To explore the differences of antibacterial effect in vitro between two different concentrations of Cefoperazone-Sulbactam (2: 1 and 1: 1) 75/30 μg (SCF105)and 75/75 μg (SCF150) upon gram-negative bacilli. Meth-ods Susceptibility test of 86 strains of clinical isolated gram-negative bacilli was conducted with K-B method using SCF105 and SCF150 respectively and the diameter of inhibition zone were measured. The Susceptibility results of two kinds of suscepti-bility sheets were analyzed and the antimicrobial results on the four common gram-negative bacillus ( Pseudomonas aeruginosa, e. Coli, klebsiella pneumoniae and acinetobacter baumannii) was explored. Results For all the 86strains, susceptibility rate and intermediate rate SCF 150 disc were 53. 5% and 26. 7%, which were significantly higher than that with SCF105 disc;the resistance rate with SCF disc was 19. 7%, significantly lower than the resistance rate of SCF105 disc (P<0. 01). Wilcox on signed rank sum test for the four kinds of clinical common gram negative bacterium ( Pseudomonas aeruginosa, Escherichia co-li, Klebsiella pneumoniae and Acinetobacter baumannii) was used and sensitivity rate with SCF150 disc was higher than the result of SCF105 disc, and the difference was significant, E. Coli (P<0. 05);For all strains and four gram negative bacteri-a, the inhibitor diameter of SCF105 disc was smaller than that of SCF150 disc (P<0. 05), and especially in E. coli (P<0. 05). Compared with the inhibitor diameter 4 kinds gram-negative bacilli, there were significant differences between SCF105 of E. Coli and Pseudomonas aeruginosa and acinetobacter baumannii);meanwhile, there were significant differences between SCF150 of E. coli and 3 other kinds (P<0. 05). Conclusion AS far as antibacterial effectiveness of gram-negative bacilli in vitro is concerned, composition ratio of 75/75μg Cefoperazone-Sulbactam is superior to that of 75/30μg Cefoperazone-Sul-bactam.