血流感染患者血液中分离的鲍曼不动杆菌同源性分析及毒力因子研究

发布时间：2018-05-10 17:17

本文选题：鲍曼不动杆菌 + 血流感染　；参考：《天津医科大学》2017年硕士论文

【摘要】：目的收集全国17家教学医院临床感染患者血液中分离的鲍曼不动杆菌,测定其对各类常见抗生素的敏感性,为医院进行感染控制和临床合理使用抗菌药物提供依据;分析全国临床流行株多重耐药鲍曼不动杆菌(Multidrug-resistant Acinetobacter baumannii,MDRAB)的同源性特点,为控制多重耐药鲍曼不动杆菌的暴发流行提供依据;对临床90株鲍曼不动杆菌进行毒力表型试验,同时检测所有菌株毒力基因的分布状况,探究毒力因子与耐药性、毒力因子与同源性的相关性;对临床分离的7株粘液表型的菌株的耐药、毒力以及同源性特点进行分析。方法收集全国17家教学医院2013年7月-2014年7月感染患者血标本中分离鲍曼不动杆菌共90株,其中包含75株多重耐药菌株和15株非多重耐药菌株。采用法国生物梅里埃公司的全自动细菌鉴定仪Vitek-2 Compact仪器及配套药敏卡对菌株进行鉴定及药敏试验,采用纸片扩散法(Kirby-Bauer,K-B)测定头孢哌酮/舒巴坦药敏。同时对分离菌株患者的年龄、性别、科室及是否曾经入住重症监护病房(Intensive care unit,ICU)进行统计分析;采用脉冲场凝胶电泳(Pulsed Field Gel Electrophoresis,PFGE)技术对90株鲍曼不动杆菌进行同源性分析;采用蹭行运动、血凝和血凝抑制试验、生物膜形成和血清杀伤试验来检测菌株毒力情况;采用聚合酶链反应(Polymerase Chain Reaction,PCR)检测D类碳青霉烯酶基因(blaOXA-23、24、51、58)和毒力基因(aba I、cus E、bap、bfm S、omp A)。结果(1)75株MDRAB多见于ICU病房,分离到49株,对头孢哌酮/舒巴坦、阿米卡星及替加环素的敏感率较高分别为69.3%、77.3%和100.0%,对其它药物的敏感率均较低,在30%以下。(2)脉冲场凝胶电泳结果显示90株鲍曼不动杆菌分为21个克隆型,分别为A-U型,MDRAB见于A-H型,非MDRAB见于I-U型,两者不存在相同克隆型别。MDRAB中A(n=51)和B(n=14)型为主要克隆型,不同医院流行的克隆型不一样,大部分医院以A克隆型为主。(3)毒力表型试验结果显示蹭行运动能力1株阳性;未发现与O型红细胞凝集的菌株,仅发现1株菌株在有无D-甘露糖存在条件下都与AB型的红细胞凝集;生物被膜形成能力阳性57株,7株粘液型菌株全部阴性;血清杀伤能力试验有71株阳性。A克隆型生物膜形成能力强于B克隆型。(4)非粘液型菌株共83株,79.4%(n=54)的多重耐药鲍曼不动杆菌毒力基因检出全部阳性。多重耐药鲍曼不动杆菌的aba I、bap、bfm S基因检出率均高于非多重耐药菌株。82.4%(n=42)的A克隆型菌株毒力基因检出全部阳性。(5)90株鲍曼不动杆菌中有7株为粘液表型,均是MDRAB,均属于B克隆型,且毒力基因检出全部阳性。其中5株来自JL医院,且抗菌药物表型和脉冲场分型完全相同,表现出对头孢哌酮/舒巴坦、左氧氟沙星、替加环素敏感,对其它抗生素均耐药的表型。另外2株分别来自NJ医院和TJ医院,抗菌药物表型与JL医院的不同。结论本研究显示临床感染患者血液中分离的MDRAB对头孢哌酮/舒巴坦、阿米卡星及替加环素耐药率较低。我国不同地区血流感染患者血液中分离的MDRAB主要流行克隆型为A型,可能存在地区之间的播散现象,这可能是我国MDRAB分离率逐渐上升的原因,提示医院应加强院内感染控制。A克隆性菌株生物膜膜形成能力强,易在医院环境中的生存和定植、导致菌株播散流行。多重耐药菌株毒力基因检出率高于非多重耐药菌株,提示临床在关注多重耐药菌株时应同时关注菌株的致病能力。粘液表型菌株可能具有更强的毒力并且易于播散,应引起临床的重视。
[Abstract]:Objective to collect the isolation of Acinetobacter Bauman from the blood of 17 clinical infection patients in the national teaching hospital, to determine its sensitivity to all kinds of common antibiotics, and to provide the basis for hospital infection control and clinical rational use of antibiotics, and to analyze the multidrug-resistant Acinetobacter (Multidrug-resistant Acinetobacte) of the national clinical epidemic strains (Multidrug-resistant Acinetobacte The homology of R baumannii, MDRAB (MDRAB) provides a basis for controlling the outbreak of multidrug-resistant Acinetobacter Bauman; the virulence phenotype test of 90 clinical strains of Acinetobacter Bauman, the distribution of virulence genes in all strains, and the correlation between virulence factor and drug resistance, virulence factor and homology, and clinical isolation The resistance, virulence and homology of 7 strains of mucous phenotype were analyzed. Methods a total of 90 strains of Acinetobacter Bauman were isolated from the blood samples from 17 teaching hospitals of China in July -2014 July 2013, including 75 multidrug-resistant strains and 15 non multidrug-resistant strains. The bacterial identification instrument Vitek-2 Compact instrument and the matching drug sensitive card were used to identify the strain and the drug sensitivity test. The drug sensitivity of Cefoperazone / sulbactam was measured by Kirby-Bauer (K-B). The age, sex, department and once the Intensive care unit (ICU) were analyzed and analyzed. Pulsed Field Gel Electrophoresis (PFGE) was used to analyze the homology of 90 Acinetobacter Bauman. The virulence of the strain was detected by rubbing movement, hemagglutination and hemagglutination test, biofilm formation and serum killing test, and the detection of D by polymerase chain reaction (Polymerase Chain Reaction, PCR). Carbapenem gene (blaOXA-23,24,51,58) and virulence genes (ABA I, cus E, BAP, BFM S, OMP A). Results (1) 75 MDRAB were found in ICU wards and separated to 49 strains. The sensitivity of Cefoperazone / sulbactam, Amikacin and tigastin was 69.3%, 77.3% and 100% respectively, and the sensitivity to other drugs was lower than 30%. (2) pulses. The results of field gel electrophoresis showed that 90 strains of Acinetobacter Bauman were divided into 21 clones, A-U type, MDRAB in A-H type, and non MDRAB in I-U type. There were no A (n=51) and B (n=14) type in the same clone.MDRAB as the main clones. The dominant clones in different hospitals were different. Most hospitals were dominated by A clone. (3) virulence phenotype. The test results showed that 1 strains of rubbing movement were positive. Only 1 strains were found to be agglutinated with AB type red blood cells under the presence of D- mannose, 57 strains positive for biofilm formation and 7 myxoid strains were negative, and 71 positive.A cloned biofilms were found in the blood clearance test. The formation ability was stronger than that of B clone. (4) 83 strains of non mucinous strain and 79.4% (n=54) of multidrug-resistant Acinetobacter Bauman were all positive. The detection rates of ABA I, BAP, BFM S in multiple drug resistant Acinetobacter spp. were all higher than those of non multidrug-resistant strain.82.4% (n=42) A cloned strain. (5) 90 strains 7 of the Acinetobacter of Acinetobacter sp., all of which are MDRAB, are MDRAB, all belong to B clone, and all of the virulence genes are positive. 5 of them are from JL hospital, and the phenotypes of antibacterial drugs and pulse field are exactly the same, showing the phenotype of Cefoperazone / sulbactam, levofloxacin, tegacycline sensitive, and other antibiotics. The 2 isolates from the NJ hospital and the TJ hospital were different from that of the JL hospital. Conclusion the study showed that the resistance rate of MDRAB to Cefoperazone / sulbactam, Amikacin and tegastin was low in the blood isolated from the patients with clinical infection. The major clone of MDRAB in the blood of patients with blood flow infection in different regions of our country was A type. There may be a phenomenon of spread between regions, which may be the cause of the gradual increase in the separation rate of MDRAB in China. It is suggested that the hospital should strengthen the hospital infection control of the membrane formation of the.A cloned strain, which is easy to survive and colonize in the hospital environment, and lead to the spread of the strain. The detection rate of virulence gene of multidrug resistant strains is higher than that of non multiple strains. Drug-resistant strains suggest that the pathogenicity of strains should be paid attention to at the same time when they are concerned with multidrug resistant strains. The mucous phenotypic strains may have stronger virulence and can be easily disseminated, and should be paid attention to.

【学位授予单位】：天津医科大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：R446.5;R515

【参考文献】