烧伤感染中阴沟肠杆菌抗性基因的定位分析

目的研究我科阴沟肠杆菌多重耐药的机理。方法通过质粒的转化和消除实验，对一株耐１２种抗菌药物的阴沟肠杆菌及其所含的８００００ｂｐ质粒进行了初步分析。结果质粒转化实验表明８００００ｂｐ质粒上至少携带有对链霉素、氨苄青霉素、羧苄青霉素、氧哌嗪青霉素、庆大霉素、妥布霉素、卡那霉素和丁胺卡那霉素等８种抗菌药物的抗性基因。质粒消除实验表明当该菌所含４种质粒（８００００、１４０００、５５００和４５００ｂｐ）全部被消除后，其所具有的１２种抗性全部消失。说明该菌对另外４种抗菌药物（头孢三嗪、头孢他啶、头孢哌酮和复方新诺明）的抗性也与其所含质粒有关。结论阴沟肠杆菌的高耐药性主要是由质粒尤其是８００００ｂｐ质粒所致，临床应做好消毒隔离工作，控制其在病区内传播

Preliminary study on multi resistant gene location of Enterobacter cloacae in burn infection

Objective\ Study the mechanisms of multi resistance to antibiotics in E.cloacae isolated from our burn patients.Methods\ Analysed one multi resistant strain (which resisted 12 antibiotics) and the 80 000 bp plasmid in it by use of plasmid transformation and plasmid removal test.Results\ There were more than eight antibiotic resistant genes in the 80 000 bp plasmid found in the plasmid transformaiton test,which were streptomycin,ampicillin,carbenicillin,piperacillin,gentamycin,tobramycin,kanamycin and amikacin. In the plasmid removal test,the resistance to 12 antibiotics was missing entirely after all the four plasmids (80 000,14 000,5 500 and 4 500bp) were removed. It showed that resistance to the other four antibiotics (ceftriaxone,ceftazidime,cefoperazone,and TMP/SMZ) was also related with the plasmids in this strain.Conlusion\ High antibiotic resistance of E. Cloacae was due to the presence of plasmids, especially the 80 000bp plasmid. It is essential to improve isolation technics in order to prevent the spread of E. cloacae infection.