多重耐药鲍曼不动杆菌的临床流行特征

Clinical and epidemiological characteristics of multidrug-resistant Acinetobacter baumannii strains

目的对西安交通大学第一附属医院收集的多重耐药鲍曼不动杆菌进行菌种确认,并检测其临床感染分布特点、耐药性及分子分型特征。方法收集经VITEK-2鉴定的多重耐药鲍曼不动杆菌47株,利用特异性引物sp2F、sp4F和sp4R通过PCR扩增的方法复检菌株;使用VITEK-2检测鲍曼不动杆菌的药物敏感性;通过多位点序列分型(MLST)方法分析临床菌株的同源性。结果经过特异性PCR扩增法确认,47株临床样本中有46株为鲍曼不动杆菌,它们大多分离自痰标本,主要收集于重症监护室,呈多重耐药性。MLST分析发现ST195、ST218、ST368及ST208共4种ST型,其中ST368与ST208亲缘关系最近。结论特异性PCR扩增法可快速、准确地鉴定鲍曼不动杆菌。本院的多重耐药鲍曼不动杆菌主要分布在重症监护室,仅对替加环素等少数抗生素有较高敏感性,存在同源性差异。

Objective To confirm the species of multidrug-resistant Acinetobacter baumannii（MRAB）strains collected from our hospital by specific PCR amplification,and further investigate their distribution,antibiotic resistance and molecular classification characteristics.Methods We collected 47 MRAB clinical strains which had been identified by VITEK-2 system,followed by species confirmation using specific primers sp2 F,sp4F and sp4 R through PCR amplification.Antibiotic resistance characteristics were detected using VITEK-2 system.And the homology of MRAB isolates was analyzed using multilocus sequence typing（MLST）.Results We confirmed 46 out of 47 strains as A.baumannii.All of them were multidrug-resistant strains,and the majority of them were found in sputum samples from patients in intensive care units（ICUs）.MLST analysis found 4 ST types,namely ST195,ST218,ST368 and ST208.The last two types had the closest genetic relationship.Conclusion Specific PCR amplification is a rapid and accurate method to identify A.baumannii.The MRAB strains in our hospital are mainly distributed in ICUs and are susceptible to only a few antibiotics such as tigecycline.