Enterobacter cloacae infection and drug sensitivity analysis in neonatal department

Objective To analyze retrospectively the infection of Enterobacter cloacae in neonatal department and its related drug sensitivity in six months from February to July in the year of 2008,to offer evidence to prevent and cure Enterobacter cloacae infection effectively.Methods To collect the general information of Enterobacter cloacae infection,the specimens positive for Enterobacter cloacae were studied,such as blood,sputum,urine,stool,cerebrospinal fluid and umbilicus secretions,Meantime,drug sensitivity for the detected Enterobacter cloacae strains was tested by disk diffusion technique(K-B method).Amp C β-lactamase and extended-spectrum β-lactamases(ESBLs) were analyzed by modified enzyme extract(cefoxitin and ceftriaxone)3-dimensional test.Results 47 cases(7.4%) of nosocomial infection were identified,and a total of 395 bacteria strains were cultured from studied specimens,the top three of which were Klebsiella pneumonia,Escherichia coli,and Staphylococcus aureus with the detection rate of 43.2%,10.6% and 8.6% respectively.However,the Enterobacter cloaca ranked eighth with 14 isolates and detection rate of 3.54%.The origins of Enterobacter cloacae were directly from sputum,blood,urine and umbilical secretions with the percentage of 64.2%,14.3%,14.3% and 7.14%,respectively.Meanwhile,the detection rates of Amp C β-lactamase producing strains and ESBLs producing strains were 21.4% and 14.2%,respectively,while the detection rate of the strains which could produce both Amp C β-lactamase and ESBLs accounts for 14.2% in our observation.The antibiotics resistance rate in β-lactamases producing strains was obviously higher than that in β-lactamases negative strains and all the strains sensitive to imipenem.Conclusions Enterobacter cloacae cannot be regarded as common bacteria causing infections in neonatal department.They often give rise to the infections of airway tract,blood,urine tract and umbilicus.It was found that Enterobacter cloacae producing AmpC enzyme or ESBLs are more common than other species.Therefore,it is achievable to get a better control of Enterobacter cloacae infection by applying imipenem at early stage.