阴沟肠杆菌致下呼吸道感染及耐药性分析

Analysis of the drug resistance and lower respiratory tract infections caused by enterobacter cloacae

目的 :探讨189例阴沟肠杆菌致下呼吸道感染的临床特征及对临床常用抗生素耐药性并测定其产β-内酰胺酶 (ESBLs)情况。方法:分析189例阴沟肠杆菌致下呼吸道感染的临床资料 ,用美国全自动微生物分析仪VITEK -IMS60进行细菌鉴定和药敏试验,用双纸片法测定其产ESBLs情况。结果:189例中年龄>60岁者78% ,67 %有基础病 ,应用抗菌素者52 % ,机体免疫力低下者31%。临床症状及胸部X线无特异性。临床分离的阴沟肠杆菌对常用抗生素的耐药率较高 ,检出产ESBLs株1株。结论:阴沟肠杆菌致下呼吸道感染多发生于有基础病、长期应用广谱抗生素、免疫力低下的老年人 ,临床表现无特异性 ,细菌耐药现象较严重 ,丁胺卡那或环丙沙星可作为治疗阴沟肠杆菌致下呼吸道感染首选药物 ,阴沟肠杆菌可产生诱导型 β-内酰胺酶 。

Objective: To investigate the clinical characteristic of 189 cases with lower respiratory tract infections caused by enterobacter cloacae and its antimicrobial susceptibility in vitro to clinical antibitics often used, and determinate its condition of producing extended spectrum β-lactamases(ESBLs).Methods: Retrospective study of the clinical material of 189 cases of lower respiratory tract infections caused by enterobacter cloacae, identificate the strains and their sensitivities to antimicrobial agents with the American full-automatic microorganism analyzer to determinate the ESBLs using double paper strip method.Results:There were 148 cases being over 60 years old in all of the 189 cases, and 67% of the whole cases suffered from underlying diseases, 52% of them were applied with multiple antibiotics, host immune suppression 31%.No specific clinical manisfection and chest X-ray appearance revealed. These isolates were highly resistant to most of clinical antimicrobial agents often used. There was one strain which produced ESBLs.Conclusion:Lower respiratory tract infections caused by enterobacter cloacae developed most common in patients of being over 60 years old who suffered from various underlying diseases, immuno-deficiency and long time antibiotics overuse.Clinical isolates were highly resistant to most kinds of antimicrobial agents, amikacin or ciprofluxacin can be the first antibiotics in therapying enterobacter cloacae infections. Moreover, enterobacter cloacae may produce induced β-lactamases, so it should be cautious of applying the third cephalosporins.