阴沟肠杆菌耐药性分析与产β-内酰胺酶及质粒介导基因型检测研究

发布时间：2018-05-22 14:31

本文选题：阴沟肠杆菌 + 耐药分析　；参考：《贵阳医学院》2015年硕士论文

【摘要】：目的:1.了解我院2008年1月-2014年12月阴沟肠杆菌的临床感染分布及对常用抗生素的耐药情况,为临床合理使用抗生素提供参考。2.明确我院阴沟肠杆菌产超广谱β-内酰胺酶(ESBLs)和头孢菌素酶(Amp C酶)及质粒介导耐药基因的分布情况,初步探讨我院阴沟肠杆菌的耐药机制。3.了解我院阴沟肠杆菌耐药株的分子流行病学特征,为进一步指导临床有效控制耐药菌株在医院内的传播提供依据。方法:1.采用WHONET 5.6软件对7年间阴沟肠杆菌株的标本来源、感染科室、年龄分布及耐药状况进行回顾性统计分析;2.收集我院2013年6月-2014年6月临床分离的非重复阴沟肠杆菌株共174株进行如下检测:①采用多底物协同-拮抗法(MSSAT)对其进行ESBLs和Amp C酶的表型检测;②PCR扩增质粒介导的ESBLs基因(TEM-1、SHV-12、CTX-M-3、SFO-1、VEB-3)、Amp C酶基因(ACT-1、DHA-1)和喹诺酮类耐药(qnr)基因(qnr A、qnr B、qnr S);③应用肠杆菌科重复一致序列(ERIC)法对携带耐药基因菌株进行分子流行病学研究,确定耐药菌株间的亲缘关系。结果:1.耐药性分析结果显示:7年间,阴沟肠杆菌对哌拉西林的耐药率最高(44.0%~69.0%);对亚胺培南耐药率最低(8.0%);2009-2013年,除了头孢曲松、亚胺培南、复方新诺明、替卡西林/克拉维酸、哌拉西林/他唑巴坦外,阴沟肠杆菌对其余10种抗生素的耐药率逐渐下降(P0.05);在各标本来源中,分泌物在阴沟肠杆菌中的绝对检出率最高;7年间共分离出1596株阴沟肠杆菌,以呼吸道标本、分泌物、尿液标本为主,尿液中的阴沟肠杆菌对抗菌药物的耐药率最高;临床感染科室主要集中在外科、内科、重症监护病房(ICU),ICU的耐药率最高;从年龄组看,感染对象以成年和老年患者居多,老年人耐药率最高,儿童组耐药率最低。2.MSSAT结果显示:174株阴沟肠杆菌中,单产Amp C酶92株(52.87%),单产ESBLs 1株(0.57%),产Amp C酶+ESBLs54株(31.03%),不产酶27株(15.52%);阴沟肠杆菌产酶株的耐药率明显高于不产酶株(P0.05),同时产Amp C酶+ESBLs菌株的耐药率高于单产Amp C酶株的耐药率(P0.05);产Amp C酶+ESBLs菌株对头孢曲松,头孢噻肟的耐药率高达98.1%与96.3%,对青霉素类的哌拉西林高达92.5%,单环类的氨曲南耐药率为88.9%,对阿米卡星耐药率较低(15.1%),对亚胺培南敏感。3.PCR结果显示:174株阴沟肠杆菌中,携带质粒介导的β-内酰胺酶基因71株,ESBLs基因检出率为31.03%(54/174),43株TEM-1、22株SHV-12、21株CTX-M-3、12株SFO-1、1株VEB-3;Amp C酶基因检出率为21.26%(37/174),22株DHA-1,17株ACT-1;71株β-内酰胺酶基因阳性菌中,仅含一种β-内酰胺酶基因的共30株,其余41株均为含两种或两种以上β-内酰胺酶基因。qnr耐药基因检出率为27.01%(47/174),qnr A 16株,qnr B 25株,qnr S 15株,其中,有9株阴沟肠杆菌同时检测到两种qnr基因;含ESBLs和(或)Amp C酶基因阳性菌株较耐药基因阴性株更易同时携带qnr基因(P0.05)。4.ERIC法将70株携带耐药基因的阴沟肠杆菌分为24型,主要的型别为X型(18株)、V型(9株)、W型(6株)。结论:1.阴沟肠杆菌对临床常用抗菌药物的耐药率呈下降趋势,对于碳青霉烯类抗生素不敏感菌株的出现应引起重视;碳青霉烯类抗菌药物依然是治疗多重耐药阴沟肠杆菌感染的首选。2.本院阴沟肠杆菌以产Amp C酶为主,同时产Amp C酶和ESBLs的菌株对第三代头孢菌素、单环类、青霉素类具有高度耐药性。3.阴沟肠杆菌同时存在不同类型的β-内酰胺酶基因和qnr基因,ESBLs耐药基因以TEM-1型为主;ESBLs和(或)Amp C酶基因阳性株可同时携带qnr基因。4.阴沟肠杆菌在医院内存在部分克隆株散在传播情况。
[Abstract]:Objective: 1. to understand the distribution of the clinical infection of Enterobacter cloacae in our hospital in December -2014 January 2008 and the resistance to common antibiotics in order to provide a reference.2. for the rational use of antibiotics in the clinic to clarify the distribution of the broad-spectrum beta lactamase (ESBLs) and cephalosporins (Amp C enzyme) and plasmid mediated resistance genes in our hospital. Study on the resistance mechanism of Enterobacter cloacae in our hospital.3. to understand the molecular epidemiological characteristics of antibiotic resistant strains of Enterobacter cloacae in our hospital in order to further guide the effective control of the spread of drug resistant strains in hospitals. Methods: 1. WHONET 5.6 software was used for the specimen origin, infection section, age distribution and distribution of Enterobacter cloacae in 7 years. A retrospective statistical analysis of the drug resistance status was carried out; 2. a total of 174 non repetitive strains of Enterobacter cloacae isolated from our hospital in June -2014 June 2013 were detected as follows: (1) the phenotypic detection of ESBLs and Amp C enzyme was carried out by multi substrate synergistic antagonistic method (MSSAT); and (2) PCR amplified plasmid mediated ESBLs gene (TEM-1, SHV-12, CTX-M-3, SFO-1, V) EB-3), the Amp C enzyme gene (ACT-1, DHA-1) and quinolone resistance (qnr) gene (qnr A, qnr B, qnr S); (3) the molecular epidemiological study of the strains carrying resistance genes was carried out by the repeated sequence of Enterobacteriaceae. Results: 1. the results of drug resistance analysis showed that 7 years, Enterobacter cloacae to piperaca. The drug resistance rate of Cilin was the highest (44.0%~69.0%), and the resistance rate to imipenem was lowest (8%); in 2009-2013 years, the resistance rate of Enterobacter cloacae to the remaining 10 antibiotics was gradually decreased (P0.05) except ceftriaxone, imipenem, compound sulfamethamine, cicillin / clavulanic acid, piperacillin / tazobactam (piperacillin / tazobactam); and secretions in the specimens were in the Yin. The absolute detection rate of Enterobacter cloacae was the highest; 1596 strains of Enterobacter cloacae were isolated in 7 years, with respiratory specimens, secretions and urine specimens, and the resistance rate of Enterobacter cloacae in urine was the highest. The clinical infection departments were mainly concentrated in surgery, internal medicine and ICU, and the rate of ICU was the highest; from the age group, the rate of drug resistance was the highest. The majority of adult and elderly patients were infected, and the drug resistance rate of the elderly was the highest, and the lowest.2.MSSAT results in the children group showed that among 174 strains of Enterobacter cloacae, there were 92 strains of Amp C, 1 (0.57%), Amp C +ESBLs54 strain (31.03%) and 27 (15.52%), and the resistance rate of Enterobacter cloacae was significantly higher than that of non production. The resistance rate of Amp C enzyme +ESBLs strain was higher than that of Amp C strain (P0.05), and the resistance rate of Amp C enzyme +ESBLs strain to ceftriaxone and cefotaxime was 98.1% and 96.3%, the penicillin piperacillin was up to 92.5%, the monosacylic amamoxan resistance rate was 88.9%, and the resistance rate of Amikacin was lower (15.1%). The results of imipenem sensitive.3.PCR showed that in 174 strains of Enterobacter cloacae, 71 strains of plasmid mediated beta lactamase gene were carried, the detection rate of ESBLs gene was 31.03% (54/174), 43 strains of TEM-1,22 strain SHV-12,21 strain SFO-1,1 strain VEB-3, Amp C enzyme gene detection rate of 21.26% (37/174), 22 strains of DHA-1,17 strains, and 71 beta lactamase genes. Among the positive bacteria, only a total of 30 strains of beta lactamase genes were contained, and the other 41 were 27.01% (47/174), qnr A 16, qnr B 25, and qnr S 15, including two or more than two beta lactamase genes, of which 9 strains of Enterobacter cloacae were detected at the same time, two qnr genes were detected, and ESBLs and / or Amp C enzyme gene positive bacteria were detected. Qnr gene (P0.05).4.ERIC method was more easy to carry 70 strains of Enterobacter cloacae carrying resistance genes into type 24, the main types were X type (18 strains), V type (9 strains), and W type (6 strains). Conclusion: 1. the resistance rate of Enterobacter cloacae to clinical antibiotics is decreasing and insensitive to carbapenems. The emergence of strains should be paid attention to; carbapenems are still the first choice for the treatment of multiple resistant Enterobacter cloacae infection in.2. our hospital, Amp C enzyme producing Enterobacter cloacae, and Amp C and ESBLs producing strains of third generation cephalosporins, mono rings, penicillins, highly resistant.3. Enterobacter cloacae at the same time Type of beta lactamase gene and qnr gene, ESBLs resistant gene is dominated by TEM-1 type, and ESBLs and (or) Amp C gene positive strain can carry the qnr gene.4. clones at the same time in the hospital memory in the spread of some clones.
【学位授予单位】：贵阳医学院
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：R446.5

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