某医院耐碳青霉烯酶类鲍曼不动杆菌耐药基因研究和同源性分析

Gene study and homology analysis of carbapenem resistant Acinetobacter baumannii in hospital

目的研究本院耐碳青霉烯酶类鲍曼不动杆菌(CRAB)的耐药基因情况,并通过基因检测分析细菌同源性,为防止院内感染、预防性用药提供依据。方法收集无锡市骨科医院2019年1—11月临床分离的56株CRAB菌株,细菌经过分离培养,采用BD Phoenix100全自动微生物分析鉴定仪进行菌株鉴定和药敏试验,并采用PCR的方法检测鲍曼不动杆菌的碳青霉烯类耐药基因,菌株的同源性分析使用肠杆菌科基因组内重复一致序列聚合酶链反应(ERIC-PCR)方法。结果56株CRAB菌株中有48株(85.7%)OXA51基因阳性,52株(92.9%)OXA23基因阳性,均未检测到OXA24及OXA58基因,对OXA23和OXA51阳性细菌进行同源性分析,38株(80.0%)属于同一基因谱。所有细菌对18种药物耐药率>95.0%,且对美罗培南,亚胺培南的耐药率均>98.0%。结论无锡市骨科医院CRAB主要为OXA23型、OXA51型菌株,且该类细菌呈多重耐药,提示临床应加强医院感染的管理,防止该类鲍曼不动杆菌的暴发传播。

Objective To investigate the epidemic situation of carbapenem-resistant genes in carbapenem-resistant Acinetobacter baumannii(CRAB)from a hospital and to analyze their homology.The homology of bacteria was analyzed by gene detection,so as to provide basis for preventing nosocomial infection and preventive drug use.Methods The non-repetitive strains of CRAB were collected from the inpatients of Wuxi Ortho-paedic Hospital from January to November 2019.The bacteria were isolated and cultured.Used BD Phoenix100 automatic microbial analysis instru-ment to carry on the strain identification and drug sensitive test,used the method of PCR to detect resistance genes,and the homology study was performed by useing enterobacterial repetitive intergenic consensus-polymerase chain reaction(ERIC-PCR)fingerprinting method.Results OXA-51 gene expression was detected in 48(85.7%)strains from the 56 strains of carbapeneme-resistant acinetobacter baumannii(CRAB),OXA-23 gene expression was observed in 52(92.9%)strains,OXA24 gene and OXA58 gene were not detected.The homology analysis of OXA51 and OXA23 positive bacteria showed that 38 strains(80.0%)belonged to the same type.The drug resistance rate of Acinetobaeter baumannii to most of antibacterials>95.0%in all drugs,and the drug resistance rate of Acinetobaeter baumannii to imipenem and meropenem were>98.0%.Conclusion The main strains of CRAB in our hospital were the bacterial strains with gene OXA23 and OXA51,the prevalent strains multiresistant.It is suggested that the management of nosocomial infection should be strengthened to prevent outbreak of CRAB.