用AFLP分型和分子标记研究鲍曼不动杆菌院内感染传播途径

Study on transmission router of Acinetobacter baumannii in Ningbo No.2 hospital by AFLP and genetic mark

目的利用AFLP分型和分子标记了解我院鲍曼不动杆菌(Acinetobacter baumannii.AB)菌株亲缘性和传播途径。方法应用PCR方法,对17种内酰胺酶基因、6种氨基糖苷类修饰酶基因、耐消毒剂和磺胺基因、整合子遗传标记(整合酶基因)、Tn21/Tn501转座子遗传标记(汞离子还原酶基因)进行检测;采用扩增片段长度多态性(Amplified Fragment Length Polymorphism,AFLP)进行AB菌分型;对检测结果作样本聚合分析讨论菌株亲缘性并根据临床资料研究AB的传播途径。结果27株AB不仅TEM、OXA-23群、ADC等内酰胺酶基因携带率高,而且包括aac(3)-Ⅰ、aa(c6′)-Ⅰ、an(t3″)-Ⅰ氨基糖苷类修饰酶编码基因,qacE△1-sul1耐消毒剂和磺胺基因,Ⅰ类整合酶基因携带率高。多基因聚合分析发现存在至少3个克隆。AFLP分型发现耐药菌是由同一个克隆进化而来。结论医院的ICU病房已经成为耐药AB菌发生、进化、传播的核心环节。加强ICU的管理工作是防止院内耐药AB菌流行的重要手段。而控制抗生素的使用,可以使AB菌的耐药性逐步减弱。

Objective To analyse the transmission router and the relationship of Acinetobacter baumannii, in Ningbo No.2 Hospital by AFLP and genetic mark. Methods The beta-lactamases gene, aminoglycosides modifying enzyme gene, disinfectants-sulfanilamide -resistant gene, int I gene and Tn21/Tn501gene were detected by PCR. The genetype was analyzed by Amplified Fragment Length Polymorphism. The relationship was analysed with cluster analysis methods. According to the clinical data, the study analysed the transmission router of AB. Results There were not only high percentages of beta-lactamases genes（TEM, OXA-23 cluster, ADC etc.） in A. baumannii isolated from Ningbo No.2 Hospital, but also high percentages of aminoglycosides modifying enzyme gene（aac（3）- Ⅰ, aac（6′）-Ⅰ , ant（3″）- Ⅰ ）, disinfectants-sulfanilamide -resistant gene and int I gene. The study find at least 3 clones by multi-gene cluster analysis methods. All of the multi-drug-resistance of A. baumannii in Ningbo No.2 Hospital evolutes from a clone. Conclusions ICU in Ningbo No.2 Hospital is the core of the arises, evolution and transmission of A. baumannii. Strengthening administration of ICU is very important to control the epidemic of multi-drug-resistance of A. baumannii. Controlling the use of antibiotics maybe decrease the multi- drug-resistance of A. baumannii