Detection of AmpC Beta-lactamase in Enterobacteriaceae and Analysis of Enzyme-mediated AmpC Resistance

OBJECTIVE To study the resistant phenotype and molecular biology character of 106 clinical isolates of Enterobacteriaceae.METHODS The 106 clinical isolates of Enterobacteriaceae were studied by agar dilution method,mutiplex PCR and DNA sequencing methods were used in further study.RESULTS The AmpC β-lactamase was detected in 35 isolates of Enterobacteriaceae(accounted for 33.02%),34 of 35 AmpC-producing isolates were resistant to cefoxitin,1 of 35 AmpC-producing isolates was intermediate-susceptible to cefoxitin,the susceptibility to cefepime and imipenem was 68.50% and 97.10%,respectively.CONCLUSIONS A new plasmid mediated AmpC β-lactamase is detected in one isolate of Enterobacteriaceae.The antibiotic resistance is closely associated with antibiotic resistance genes.