我院流行鲍曼不动杆菌OXA及AmpC酶基因型分析

Genotype of OXA and Amp C Beta-lactamases in Acinetobacter baumannii in our hospital

目的分析我院鲍曼不动杆菌(acinetobacter baumannii,AB)耐药相关基因β-内酰胺酶(OXA、Amp C)及插入序列(ISAba1)的携带情况,为地区流行病学及抗菌药物的合理应用提供依据。方法收集2013年9月—2014年9月佳木斯大学附属第一医院临床分离鲍曼不动杆菌,VITEK-II测试系统菌种鉴定及药敏检测,并进行16SrRNA鉴定;多重PCR检测鲍曼不动杆菌携带的相关耐药基因bla OXA-23、bla OXA-24、bla OXA-51、bla OXA-58、bla ADC、bla DHA及插入序列ISAba1。结果鲍曼不动杆菌对头孢哌酮/舒巴坦、亚胺培南、美洛培南的耐药率分别为12.5%、36.7%、38.5%。66株(95.7%)携带bla OXA-51基因,32株(46.4%)携带bla OXA-23基因,53株(76.8%)携带bla ADC基因,34株(49.3%)携带ISAba1插入序列。碳青霉烯类耐药的鲍曼不动杆菌中,22株(84.6%)携带bla OXA-23,其中19株(73.1%)上游检测到ISAba1,24株(92.3%)携带bla ADC,其中10株上游检测到ISAba1。结论产bla OXA-23、bla ADC型β-内酰胺酶可能是我院鲍曼不动杆菌耐药的主要原因,插入序列(ISAba1)可能增强水解酶表达从而加强耐药。

Objective To discuss the distribution of carbapenem-resistant related genes （ OXA and AmpC Beta-lactamases） and ISAbal in Acinetobacter baumannii（AB） in our hospital ,and provide a reasonable basis for the selection of anti- microbial drugs. Methods Clinical specimens were collected at the First Affiliated Hospital of Jiamusi University from September 2013 to September 2014. The VITEK-II automated microbial identification/susceptibility testing machine was used to select 69 cases of A. baumannii and 16SrRNA was detected. Multiplex PCR detection method was used to identify Acinetobaeter baumannii carrying carbapenem related resistant genes blaOXA-23 ,blaOXA-24, blaOXA-51, blaOXA-58, blaADC, blaDHA and ISAbal, and resistance genes of the positive amplified products were subjected to DNA sequence analysis. Results The selected 69 AB samples showed the resistant rate of SCF, IMP and MEM were 12.5% ,36.7% and 38.5%, respectively. Sixty-six （95.7%） carrying blaOXA-51,32 （46.4%） carrying blaOXA-23,53 （76.8%） carrying blaADC and 34 （49.3%） carrying ISAbal. Out of 26 carbapenem resistant strains of Acinetobaeter baumannii identified, 22 （ 84.6% ） carried blaOXA-23, including 19 strains （73.1% ） of the upstream detected ISAbal, 24 （ 92.3% ） carried blaADC,including 10 strains of upstream ISAbal detected. Conclusion The blaOXA-23 and blaADC may be responsible for the main reason of Acinetobacter baumannii carbapenem antimicrobial enzyme resistance.