下呼吸道医院感染阴沟肠杆菌耐药性及分子生物学特性研究  

Study of Drug-Resistance and Molecular Biological Characteristic of Enterobacter cloacae

作　　者：李萍[1] 李桂琴[1] 金炎[1] 肖平[1] 郑秀兰[1] 伊长英[2] 

机构地区：[1]山东省立医院,山东济南250021 [2]山东省济南市儿童医院,山东济南250000

出　　处：《中华医院感染学杂志》2001年第4期258-261,共4页Chinese Journal of Nosocomiology

基　　金：山东省卫生厅科研基金资助课题

摘　　要：目的　掌握下呼吸道医院感染阴沟肠杆菌耐药谱及分子流行病学特征。方法　耐药谱选用改良 K- B法和MIC、Alkalin lysis小量快速提取质粒 ,经琼脂糖电泳获得细菌质粒 DNA图谱 ,用限制性核酸内切酶 Hind 、Eco R 、Bgl 、Bam H 分别酶切细菌染色体 DNA ,凝胶电泳及拍照等。结果　呼吸病区 10名下呼吸道感染患者和环境的分离菌株均耐 CB、AP、CZ、FT,对 AP、CZ的最小抑菌浓度均 >12 8μg/ ml,而烧伤患者分离菌耐 10种抗生素 ;感染患者菌质粒 DN图谱显示 2 .3、2 .7、3.5 MD3条质粒带 ,不同于其他菌 ;4种限制性核酸内切酶分别酶切染色体 DNA,在同种酶切图谱中 ,感染患者和环境分离菌的酶切带相同 ,而烧伤患者菌不同。结论　 3种分型技术联合应用 ,证明此次下呼吸道感染流行 EC属同一克隆菌 ;传播途径主要为消毒不彻底的氧气设施 ;此方法准确、可靠、特异性强 ,为控制和预防下呼吸道医院感染、追踪传染源、切断传播途径提供遗传学信息 ,对临床医生选用敏感有效抗生素起指导作用。OBJECTIVE To study the type of drug resistance spectrum and molecular biological characteristic of Enterobacter cloacae whch infected lower respiratory tract in hospital. METHODS K B method and MIC are adopted to get drug resistance spectrum, and alkaline lysis was chosen to extract small quantity of plasmid rapidly in order to get plasmid diagram. The chromosomal DNA was firstly cut by restriction endonuclease Hind Ⅲ, EcoR Ⅰ, Bg l Ⅰand BamHⅠ, separately, then the restriction fragmeats were separated through electrophoresis. RESULTS The bacterial strains separated from 10 patients with respiratory infection and the environment could endure CB, AP, CZ and FT. The MIC titer to AP, CZ was more than 128 μg/ml. But the E.cloacae from the burned patients could stand 10 kinds of antibiotics separately. The plasmid diagram of patients with infection showed 3 plasmid hands which were of 2.3, 2.7, 3.5 MD. respectively. Those were different from the E.cloacae separated from the burned patients bacteria. In the same kind of restriction diagram obtained by cutting 4 kinds of restriction endonuclease separately, the E.cloacae separated from 10 infected patients and the environment has the same electrophoretic bands while the bacteria from the burned patients are different. CONCLUSIONS By combining the three kinds of techniques it can be verified that this epidemic infection of E.cloacae was caused by the some clone bacteria which were disseminated by the oxygen supplying equipment that were not disinfected thoroughly. This method is accurate, reliable and has high specificity. It can′t only provide genetic information for controlling, preventing hospital infection and tracing the infection source and the way of dissemination but also direct the clinical doctors to select sensitive antibiotics.

关 键 词：医院内感染 阴沟肠杆菌 耐药性 质粒DNA图谱 限制性核酸内切酶图谱 

分 类 号：R378.2[医药卫生—病原生物学]