耐药志贺菌1类整合子的研究  

Analysis of class 1 integrons in drug-resistant shigella

作　　者：郑晓燕[1] 温艳[1] 阴赪宏[1] 黄敏君[1] 李威[1] 栗绍刚[1] 齐志群[1] 

机构地区：[1]首都医科大学附属北京友谊医院北京热带医学研究所,北京100050

出　　处：《中国病原生物学杂志》2007年第6期409-412,共4页Journal of Pathogen Biology

基　　金：北京市自然科学基金资助项目(No.7052026);中华医院管理学会/默沙东-医院管理科研课题(No.2004KY01)

摘　　要：目的分析我院志贺菌的流行菌株类型和耐药特点,研究志贺菌1类整合子的检出率、与耐药的相关性及其携带的耐药基因盒。方法从本院肠道门诊腹泻患者的粪便标本分离出70株志贺菌,以K-B琼脂法测定药敏情况;PCR扩增1类整合子可变区并进行序列测定和基因盒分析。结果70株志贺菌对四环素、复方新诺明、氨苄西林、利福平、萘啶酸的耐药率均>60%;对喹诺酮类常用药诺氟沙星耐药率较低,为12.8%;对头孢菌素类的耐药率≤10%。多重耐药率较高,达到77.1%。16株(22.9%)志贺菌中检出1类整合子。其中8株检出大小约为1 900 bp的1类整合子,测序显示含有编码对甲氧苄啶耐药的基因盒dhfrXⅡ和对氨基糖苷类耐药的基因盒aadA2,另8株检出大小约为1 000 bp的1类整合子,测序显示含有编码对氨基糖苷类耐药的基因盒aadA2。结论本院志贺菌流行株主要是福氏和宋内氏志贺杆菌,多重耐药率较高。志贺菌中存在1类整合子。Objective To analysis the epidemic serotypes of Shigella and their antibiotic resistant characteristics in our hospital. To investigate class 1 integrons in shigella, their association with drug resistance in shigella and the gene cassettes they carried. Methods The stool samples of the patients with diarrhea were collected and the bacteria isolation, culture, and systemic serotype identification were made. At the same time, antimicrobial susceptibility testing was performed in Kirby-Bauer agar dilution method. Amplify the variable regions of class 1 integrons by PCR, sequencing and analysis gene cassettes they carried. Results Of the 70 strains of Shigella detected, 37 were group B （Shigella flexneri） and 33 group D （Shigella sonnei）. More than 60% of the Shigella strains tested were resistant to Tetracycline, Trimethoprim-sulfamethoxazole, Ampicillin, Rifampicin, Nalidixinic acid. But the resistant rate of Shigella strains to Norfloxacin is 12.8%, and the resistant rate to cephalosporin is no higher than 10%. Multidrug resistant rate is 77. 1%. 16 （22.9%） isolates carried class 1 integrons. 8 （11.4%） isolates of them had a class 1 integron, which was 1 900 bp in size. Upon sequencing the entire integrons, 2 different gene cassettes were found, including genes encoding for resistance to trimethoprim （dhfrXⅡ） and aminoglycosides （aadA2）. 8 （11.4%）isolates of them had a class 1 integron, which was 1 000 bp in size and carried a gene cassette encoding for resistance to aminoglycosides （aadA2）. Conclusion In our hospital, the main serotypes of Shigella spp were S flexneri and S sonnei. Multidrug-resistant rate of shigella was very high. Class 1 integrons were existed in shigella,and had association with drug resistance.

关 键 词：整合子 志贺菌 耐药 

分 类 号：R378.25[医药卫生—病原生物学]