In Vitro Analysis of Activities of 16 Antimicrobial Agents against Gram-Negative Bacteria from Six Teaching Hospitals in China

Abstract

SUMMARY:To evaluate the in vitro antimicrobial activities of biapenem, arbekacin, and cefminox against different gram-negative bacterial isolates in China, a total of 100 non-duplicated Escherichia coli, 100 Acinetobacter baumannii, 100 Pseudomonas aeruginosa, and 99 Klebsiella pneumoniae isolates were collected from 6 teaching hospitals in China in 2012. The minimal inhibitory concentrations (MICs) of biapenem, arbekacin, cefminox and 13 other antibiotics were determined by the broth microdilution method. The carbapenems (biapenem, meropenem, and imipenem) exhibited high antimicrobial activity against E. coli (98z) and K. pneumoniae (95z), followed by colistin and amikacin. The MIC 50 and MIC 90 of biapenem against E. coli were 0.06 mg/L and 0.25 mg/L, respectively. For K. pneumoniae, the MIC 50 and MIC 90 of biapenem were 0.25 mg/L and 1.0 mg/L, respectively. The MIC 50 and MIC 90 of cefminox against E. coli were 1.0 mg/L and 4.0 mg/L, respectively. The resistance rates of A. baumannii to most of the antibiotics were more than 50z, except for colistin. Amikacin was the most active antibiotic against P. aeruginosa (97z), followed by colistin (93z). The MIC 50 and MIC 90 of arbekacin against P. aeruginosa were 2.0 mg/L and 8.0 mg/L, respectively. In conclusion, carbapenems, colistin, amikacin, and arbekacin exhibited high antimicrobial activities against gramnegative bacteria, except A. baumannii.

Comparative Study of Different Methods of Detection of β-lactamase Production in Gram Negative Bacterial Isolates and Studying Induction of Resistance to Cefipime

“…Our results are similar, to some extent, to those reported by Jones et al (Jones et al, 2002), Iroha et al(Iroha et al, 2015), Cho et al(Cho et al, 2015), Chen et al(Chen et al, 2015) who found that carbapenems (biapenem, meropenem and imipenem) exhibited high antimicrobial activities against Gram-negative bacteria especially E. coli and Klebsiella pneumoniae. Also Turner examined the activity of meropenem against a total of 5208 isolates of Enterobacteriaceae; the susceptibility rate for meropenem was (99.4%).…”

Optimal dosing regimen of biapenem and fosfomycin sodium combination against multidrug resistant Acinetobacter baumannii infection in pediatric patients using Monte Carlo simulation

“…However, the results of these studies showed that biapenem combined with fosfomycin yielded higher percentage of synergism than the other carbapenems (biapenem 34.18%, imipenem 29.11%, meropenem 27.43% and doripenem 23.63%). The higher MIC50 and MIC90 of A. baumannii for biapenem and fosfomycin in teaching hospitals were consistent with studies in China [27][28] .…”

High Prevalence of Colistin Resistance and mcr-1 Gene in Escherichia coli Isolated from Food Animals in China

“…Though colistin exhibited high antimicrobial activities against GNB, including E. coli, A. baumannii, Pseudomonas aeruginosa isolates, and K. pneumonia in human (Chen et al, 2015), the frequent presence of mcr-1 -positive E. coli and in food animals might be a threat to human. As colistin is the last therapeutic option against infections caused by MDR GNB, careful monitoring of the evolution of colistin resistance and the spread of mcr-1 gene in isolates from humans in China is urgently needed.…”