ICU多耐药肺炎克雷伯菌整合子及耐药基因研究

Study on integrons and drug-resistant genes of multidrug resistant Klebsiella pneumoniae in ICU

目的研究ICU多耐药肺炎克雷伯菌的整合子及其耐药基因情况。方法收集宁波市医疗中心李惠利医院2019年ICU来源多耐药肺炎克雷伯菌30株,统计分析药敏结果;多重PCR检测Ⅰ类、Ⅱ类、Ⅲ类整合酶基因及整合子可变区,进一步对整合子阳性菌株的可变区进行测序分析。结果30株多耐药肺炎克雷伯菌对多种抗菌药物(头孢类头孢唑林、头孢曲松,氨基糖苷类阿米卡星、庆大霉素,磺胺类甲氧苄氨嘧啶)的耐药率均超过70%;均检出Ⅰ类整合酶基因,未检出Ⅱ类、Ⅲ类整合酶基因;23株菌基因盒PCR扩增阳性,扩增片段大小为1904 bp~1929 bp,均为dfrA12-orf-aadA2基因盒。结论本地区ICU多耐药肺炎克雷伯菌很可能普遍含有Ⅰ类整合子及基因盒dfrA12-orf-aadA2,需加强耐药监测合理使用抗菌药物。

Objective To study the integrons and drug-resistant genes of multidrug resistant Klebsiella pneumonia(K.pneumoniae)in ICU.Methods In total,30 strains of multi-drug resistance K.pneumonia were collected in Ningbo Medical Center Lihuili Hospital.The classⅠ,Ⅱ,Ⅲintegrons and the variable regions of integrons were analyzed by PCR and sequencing.Results The drug resistance rate of 30 strains of multidrug-resistant Klebsiella pneumoniae to multiple antibiotics(cefazolin,ceftriaxone,aminoglycoside amikacin,gentamicin,sulfamethoprim)was more than 70%.Ⅰclass integrase genes were detected,butⅡ,Ⅲintegrase genes were not detected;the 23 strains were positive for PCR amplification,and the size of the amplified fragments ranged from 1904 bp to 1929 bp,all of which were dfrA12-ORF-aadA2 gene boxes.Conclusion ICU multi-drug resistance K.pneumonia carry classⅠintegron and dfrA12-orf-aadA2 resistance gene cassettes in this area,and the monitoring of drug resistance strains should be strengthened.