Detection of AmpC ?-Lactamases in Escherichia coli and Klebsiella pneumoniae / 中华医院感染学杂志

ABSTRACT

OBJECTIVE To study the AmpC ?-lactamases form clinical isolates of Escherichia coli and Klebsiella pneumoniae in our hospital.METHODS Using confirmatory test recommended by the NCCLS to detect ESBLs produced by 369 strains E.coli and K.pneumoniae,adopting three-dimensional test was performed and three-dimensional depression test and AmpC ?-lactamases inducing test to detect the phenotype of screening strains producing AmpC ?-lactamases.RESULTS Among 73 strains whose phenotypes doubted of production of AmpC ?-lactamases 34 were AmpC ?-lactamases producing strains,of which 24 strains were E.coli and 10 strains were K.pneumoniae.Five E.coli strains and 2 K.pneumoniae strains produced ESBLs and AmpC ?-lactamases.At AmpC ?-lactamases inducing test,2 K.pneumoniae strains produced AmpC ?-lactamases.CONCLUSIONS AmpC ?-lactamases are the another most important resistance mechanisms of E.coli and K.pneumoniae,much attention should be paid to their detections and surveillance,it will direct the clinics to use antibiotics reasonably,relieve the selective pressure of bacteria resistance and avoid the nosocomial infection.