肠杆菌科细菌KPC型碳青霉烯酶的研究

目的了解某院临床分离的肠杆菌科细菌产KPC型碳青霉烯酶情况及其基因型别。方法收集该院2009—2010年临床分离的肠杆菌科细菌1 801株,经药敏试验筛选出耐药性高的菌株,采用改良Hodge试验和聚合酶链反应(PCR)扩增检测细菌产KPC型碳青霉烯酶情况,并测序分析其基因型别。结果 1 801株肠杆菌科细菌中,有783株(43.48%)对第三代头孢菌素耐药,其中4株还对碳青霉烯类抗菌药物耐药;改良Hodge试验初筛出2株耐药菌株,经PCR扩增证实为碳青霉烯酶blaKPC-2基因。结论该院已出现产KPC-2型碳青霉烯酶耐药基因的肠杆菌科细菌,临床与实验室应加强监测和控制。     

产气肠杆菌中首次发现碳青霉烯酶KPC-2型

目的调查1株耐碳青霉烯类产气肠杆菌中β-内酰胺酶基因的存在情况。方法收集1株耐碳青霉烯类产气肠杆菌,先用改良三维试验检测β-内酰胺酶活性,用改良Hodge试验检测产碳青霉烯酶表型,再用聚合酶链反应(PCR)的方法分析A、B、C、D 4类40种β-内酰胺酶基因。结果改良三维试验和改良Hodge试验分别检出耐碳青霉烯类产气肠杆菌的β-内酰胺酶活性,β-内酰胺酶基因检出KPC-2型(GenBank登录号:JF434018)和TEM-1型,其他基因均未检出。结论该株产气肠杆菌耐碳青霉烯类药物与细菌产这2种β-内酰胺基因相关,在产气肠杆菌中查出KPC-2型基因为国内外首次。     

耐碳青霉烯类抗菌药物的肠杆菌科细菌耐药性与分子特征分析

目的了解对碳青霉烯类抗菌药物不敏感的肠杆菌科细菌的发生及耐药情况,探讨耐药与产酶的关系。方法选取2011-2012年医院亚胺培南或美罗培南不敏感的肠杆菌科细菌15株,用琼脂稀释法测定最小抑菌浓度(MIC),改良Hodge试验和EDTA纸片协同试验筛选产碳青霉烯酶表型;PCR检测碳青霉烯酶基因及其他β-内酰胺酶基因,多位点序列分型(MLST)进行分子分型及同源分析。结果共收集碳青霉烯类抗菌药物不敏感肠杆菌科细菌15株;多黏菌素B和替加环素敏感性较高,均>90.00%;肺炎克雷伯菌、大肠埃希菌和黏质沙雷菌均检出产KPC酶菌株,占73.33%;11株产KPC酶菌中10株为KPC-2+ESBLs,1株为KPC-2+AmpC,其中3株为KPC-2+ESBLs+AmpC,4株非产KPC酶菌株中有2株ESBLs+AmpC,各有1株仅检测到ESBLs或AmpC酶,未检测到产金属酶及OXA酶菌株;MLST分型以ST11为主,共4株。结论医院产KPC-2酶细菌以肺炎克雷伯菌最多,产KPC菌株同时携带多种耐药基因与高度耐药相关;ST11型为医院优势流行型别。     

耐碳青霉烯类肠杆菌科细菌的耐药基因研究

目的调查分析医院耐碳青霉烯类肠杆菌科细菌分布、耐药性及耐药基因的携带,为耐碳青霉烯类肠杆菌科细菌感染的抗菌药物合理选用、遏制其持续感染和暴发流行提供依据。方法收集医院2009-2013年临床分离6 132株肠杆菌科细菌,采用聚合酶链反应(PCR)法检测耐碳青霉烯类肠杆菌科细菌相关耐药基因KPC、IMP、VIM、NDM、OXA,并测序分析基因型别,数据采用SPSS 17.0软件进行统计分析。结果 6 132株肠杆菌科细菌中检测到27株耐碳青霉烯类肠杆菌科细菌,检出率为0.44%;耐碳青霉烯类肠杆菌科细菌除对阿米卡星和妥布霉素的耐药率分别为3.70%和25.93%外,对大多数临床常用抗菌药物呈高度耐药;27株耐碳青霉烯类肠杆菌科细菌均扩增出碳青霉烯酶基因,其中KPC阳性13株占48.15%、IMP阳性13株占48.15%、VIM阳性8株占29.63%、OXA阳性3株占11.11%。结论产碳青霉烯酶是临床分离耐碳青霉烯类肠杆菌科细菌的重要耐药机制,且主要为KPC和IMP基因型,在临床加强对耐碳青霉烯类肠杆菌科细菌产碳青霉烯酶的监测和控制十分重要。     

耐碳青霉烯类肠杆菌科细菌KPC-2与NDM-1基因的研究

目的检测耐碳青霉烯类抗菌药物肠杆菌科细菌产酶情况以及KPC-2和NDM-1耐药基因的检出,分析耐碳青霉烯类抗菌药物的耐药机制。方法采用改良Hodge试验、亚胺培南-EDTA纸片协同试验和AmpC酶三维试验检测29株耐碳青霉烯类抗菌药物肠杆菌科细菌产酶情况;PCR法检测KPC-2及NDM-1两种碳青霉烯酶耐药基因。结果 29株分离菌中26株菌改良Hodge试验阳性,7株亚胺培南-EDTA纸片协同试验阳性,7株AmpC酶三维试验阳性,16株携带KPC-2型碳青霉烯酶耐药基因,占55.17%,未扩增出NDM-1碳青霉烯酶耐药基因。结论耐碳青霉烯类抗菌药物肠杆菌科细菌的耐药机制主要是产碳青霉烯酶。     

新生儿重症监护室分离的碳青霉烯类耐药阴沟肠杆菌的分子流行病学

目的探讨引起新生儿重症监护室患儿医院感染的阴沟肠杆菌病原学特点。方法收集2013年8月-2015年6月青岛大学附属医院临床分离的8株非重复的耐碳青霉烯类阴沟肠杆菌,采用Vitek-2 Compact系统进行菌株的鉴定和药敏。亚胺培南复合E条检测菌株的金属酶。PCR扩增及产物测序检测菌株携带的碳青霉烯酶及其他β-内酰胺酶基因。通过多位点序列(MLST)和脉冲场凝胶电泳(PFGE)验证菌株克隆聚集性。质粒接合、基于PCR的分型和S1核酸酶切的Southern杂交检测质粒的特性。结果 8株阴沟肠杆菌(YG1～YG8)对目前常用的头孢菌素和碳青霉烯类抗菌药物均耐药,且均携带bla_(NDM-1)基因。接合实验显示8株阴沟肠杆菌可将携带的质粒转移到大肠J53Azi~R受体菌,且供体菌与其接合子的金属酶试验均阳性。ST177型阴沟肠杆菌(YG5～YG7)3株PFGE条带数目及位置相同,属于克隆A;属于克隆B的YG3和YG4菌株为ST231型;属于克隆C、D和E的YG1、YG2和YG8菌株的MLST分别为ST418,ST190和ST592型。Southern杂交显示供体菌YG5携带两个质粒,大小约50 kb和400 kb,而其接合子YG5C携带大小约50 kb的质粒。结论携带bla_(NDM-1)阴沟肠杆菌在新生儿重症监护室的患儿中存在多克隆的流行。经检索,ST177型阴沟肠杆菌引起新生儿的医院感染属于国内外首次报道。     

耐碳青霉烯类肠杆菌198株临床分离株耐药性及其耐药基因

目的 分析耐碳青霉烯类肠杆菌(CRE)耐药现状并检测其相关耐药基因,为临床治疗CRE感染,合理使用抗菌药物提供参考。方法 收集复旦大学附属中山医院2020年1月-2021年12月患者临床标本分离的耐碳青霉烯类肠杆菌非重复分离株共198株,使用肉汤微量稀释法检测分离株对临床常用的抗菌药物的最低抑菌浓度,并通过聚合酶链反应对CRE的碳青霉烯酶进行相关耐药基因的检测。结果 198株CRE菌株中,165株产blaKPC占83.33%,20株产blaNDM占10.10%,3株产blaIMP占1.52%,还有2株同时产blaKPC+NDM占1.01%。本研究中产丝氨酸酶的CRE菌株对头孢他啶/阿维巴坦(CZA)敏感率为100.00%,产金属酶的CRE菌株对CZA敏感率为0,此外CRE对黏菌素和替加环素的敏感率均>90%。结论 和其他临床常用抗菌药物相比,黏菌素和替加环素对产碳青霉烯酶的肠杆菌目细菌具有较好的体外抗菌活性,此外头孢他啶/阿维巴坦对产丝氨酸酶的CRE菌株也具有较好的抗菌活性。     

临床分离耐碳青霉烯类阴沟肠杆菌的耐药机制和同源性分析

目的 分析临床分离耐碳青霉烯类阴沟肠杆菌的耐药机制和同源性,为治疗及医院感染控制提供数据支持。方法 对2019年成都市龙泉驿区第一人民医院临床分离的所有阴沟肠杆菌进行药物敏感试验。同时采用碳青霉烯酶抑制剂增强试验对耐碳青霉烯类阴沟肠杆菌进行耐药表型检测,采用PCR技术进行耐药基因检测,采用肠杆菌目基因间重复序列引物PCR技术进行同源性分析。结果 2019年临床标本共检出43株阴沟肠杆菌,其中耐碳青霉烯类阴沟肠杆菌(CRECL)11株,主要来源于重症医学科,主要分离自痰液标本。耐碳青霉烯类阴沟肠杆菌对头孢类抗菌药物的耐药率高于80%,对喹诺酮类的耐药率则低于30%。耐碳青霉烯类阴沟肠杆菌的耐药表型主要为同时产A类碳青霉烯酶和B类碳青霉烯酶,耐药基因主要为bla_(KPC)和bla_(NDM),未检出D类耐药基因。11株耐碳青霉烯类阴沟肠杆菌可分为5型,其中最多的基因型有6株,这6株菌主要分离自重症医学科和重症医学科转科密切的相关科室。结论 耐碳青霉烯类阴沟肠杆菌对多数抗菌药物的耐药率高,耐药基因以bla_(KPC)和bla_(NDM)为主,11株耐碳青霉烯类阴沟肠杆菌可分为5型,而且多株同一型别在医院出现,应加强监测,严格落实各项消毒隔离措施,严防耐碳青霉烯类阴沟肠杆菌引发院内感染和播散流行。     

儿童感染耐碳青霉烯酶肠杆菌耐药基因及临床分析

目的 检测儿童感染耐碳青霉烯酶肠杆菌科细菌耐药基因并分析其临床资料,以了解儿童耐碳青霉烯肠杆菌感染的高危因素.方法 通过药敏分析筛选出医院患儿的多药耐药肠杆菌科细菌;采用PCR法检测编码碳青霉烯酶的耐药基因与编码产超广谱β-内酰胺酶(ESBLs)的耐药基因;回顾性分析耐碳青霉烯酶肠杆菌感染患儿的临床特点、治疗经过及预后.结果 分离出6株来自感染患儿送检标本分离的耐碳青霉烯酶肠杆菌科细菌,药敏试验显示,对几乎所有碳青霉烯类及β-内酰胺类抗菌药物耐药,仅对部分喹诺酮类及氨基糖苷类抗菌药物敏感;均携带碳青霉烯酶耐药基因与1～2种ESBLs耐药基因;6例患儿长时间使用广谱抗菌药物,均存在相应感染部位;其中4例由外院转诊;收入院时5例病程迁延较长;5例存在基础疾病;除1例死亡和1例失访外,3例痊愈,1例反复感染间断接受治疗.结论 儿童耐碳青霉烯酶肠杆菌科菌株临床感染病例大多存在基础疾病、较长时间使用广谱抗菌药物(特别是碳青霉烯类)等,可能为其高危因素,尽早明确病原耐药变化,并根据药敏试验选择适宜抗菌药物对改善其预后具有重要意义.     

Carba NP试验及CIM试验检测肠杆菌科细菌碳青霉烯酶的性能评估

目的评估Carba NP试验(CNPt)及碳青霉烯类失活(CIM)试验在碳青霉烯类耐药肠杆菌科细菌中检测碳青霉烯酶的性能及临床价值。方法收集南京医科大学附属无锡市第二人民医院2014—2015年临床分离的各种标本碳青霉烯类耐药肠杆菌科细菌菌株92株,同时选取碳青霉烯敏感的菌株90株作为对照组。所有菌株进行碳青霉烯酶耐药基因PCR检测、碳青霉烯类失活(CIM)试验、CNPt、改良Hodge试验(MHT)检测。结果 92株碳青霉烯类耐药肠杆菌科细菌包括产碳青霉烯酶肠杆菌87株及非产碳青霉烯酶肠杆菌5株;87株产酶株中79株产A组酶;8株产B组酶,未检测到D组的碳青霉烯酶。CNPt与CIM试验诊断菌株是否产碳青霉烯酶的敏感性和特异性均为100%;MHT实验诊断菌株是否产碳青霉烯酶敏感性为96.5%,特异性为98.9%。结论 CNPt及CIM试验能快速、准确筛查出临床分离鉴定的产碳青霉烯酶的肠杆菌科细菌,在常规的微生物实验室有发展前景,可作为表型确认试验和耐药监测的手段。     

Risk factors for infection and molecular typing in patients in the intensive care unit colonized with nosocomial Enterobacter aerogenes.

OBJECTIVES: To determine the frequency of colonization by Enterobacter aerogenes in patients in the intensive care unit (ICU) for more than 48 hours and to evaluate the risk factors for infection in patients colonized by this bacteria. DESIGN: An 8-month prospective study. SETTING: A 12-bed medical-surgical ICU in a 450-bed, university-affiliated, tertiary-care hospital in Belgium. METHOD: Pulsed-field gel electrophoresis was used to determine the genotypes of E. aerogenes isolates. RESULTS: We observed two major clones of E. aerogenes in the ICU. Interestingly, 87.5% of infected patients had the same genomic profile for colonization and infection. Risk factors for infection in this particular population included younger age, prolonged hospital stay, mechanical ventilation, and bronchoscopy. CONCLUSIONS: Colonization is a major prerequisite for infection. The identification of risk factors for infection in colonized patients can optimize the quality of treatment in the ICU.     

产气肠杆菌的临床分布及耐药性分析

目的 了解医院感染产气肠杆菌在临床的分布及其耐药现状,为临床合理使用抗菌药物提供依据.方法 对近3年临床分离的138株产气肠杆菌,用K-B法检测对16种抗菌药物的耐药性,用三维试验检测AmpC酶和ESBLs.结果 菌株分离最多的临床科室是ICU、烧伤科、呼吸内科、泌尿外科和肝胆外科;检出率最高的标本是痰液、咽拭子、血液和创面;产气肠杆菌对青霉素类和三代头孢菌素的耐药率74.6％～99.3％,四代头孢菌素的耐药率也高达53.6％,未发现对亚胺培南和美罗培南耐药株,头孢哌酮/舒巴坦和哌拉西林/他唑巴坦耐药率仅为8.0％和25.4％;此外,喹诺酮类药物药耐率较低,为2.9％～5.1％,氨基糖苷类药物在17.4％～48.6％,磺胺甲恶唑/甲氧苄啶的耐药率为74.6％;三维试验产ESBLs菌和产AmpC的检出率分别为22.5％和29.7％,有13株菌同时产ESBLs和AmpC酶.结论 产气肠杆菌已成为医院感染重要病原菌之一,且耐药率日趋严重,对高危病区应完善和落实各项预防措施,严格无菌操作,加强对易感患者的监测.     

Molecular and descriptive epidemiologyof multidrug-resistant Enterobacteriaceae in hospitalized infants.

OBJECTIVE: To investigate the epidemiology of multidrug-resistant Enterobacteriaceae (MDRE) in hospitalized infants. METHODS: From 2000 through 2005, active surveillance cultures for MDRE were performed for patients admitted to a 40-bed neonatal intensive care unit (NICU) that provides care for critically ill infants 6 months of age or younger. MDRE epidemiology and the genetic relatedness of MDRE strains determined by repetitive-sequence polymerase chain reaction were analyzed. RESULTS: Active surveillance cultures revealed that 759 (23%) of 3,370 NICU infants (or approximately 1 in 5) developed MDRE colonization or infection and that 613 (72%) of the 853 isolates with epidemiologic data available were healthcare acquired. MDRE colonization occurred more frequently (in 653 infants [86%]) than did MDRE infection (in 106 [14%]). Of the 653 infants with MDRE colonization, 119 (18%) eventually became infected, with 29 (4%) acquiring sterile site infections. The most commonly isolated organisms were the Enterobacter species, accounting for 612 (71%) of the 862 isolates. Molecular epidemiologic analysis revealed that genetic-relatedness clustering (related clusters defined as having a genetic similarity coefficient greater than 95%) varied depending on microbial species. Clustering was detected for 36 (78%) of the 46 Enterobacter aerogenes isolates, 22 (45%) of the 49 Enterobacter cloacae isolates, and 13 (59%) of the 22 Klebsiella pneumoniae isolates. CONCLUSION: Hospitalized infants are at significant risk of acquiring MDRE, specifically Enterobacter species, at the study institution. Active surveillance cultures identified colonized patients who likely contributed to the institutional reservoir of MDRE. Molecular epidemiologic studies suggest that both patient-to-patient transmission and de novo acquisition of resistance play a role in the acquisition of these organisms, and that the clinical significance of such acquisition varies by species. The high percentage of E. aerogenes isolates that demonstrated genetic clustering suggests that monitoring the prevalence of this organism could serve as a useful measure of compliance with infection control procedures.     

RAPD用于新生儿病房产气肠杆菌分子流行病学研究

目的 建立产气肠杆菌RAPD技术,用于新生儿病房产气肠杆菌分子流行病学研究.方法 在具有10张床位的新生儿病房,于同一时间采自4例同期住院患儿分离出5株产气肠杆菌,做RAPD分析及药敏试验,找出流行相关菌株及分析耐药情况.结果 两株具有相同RAPD指纹图谱的产气肠杆菌是流行相关菌株,分别采自住院第4天和第10天的两例患儿,在新生儿病房内获得;所有菌株不同程度地对氨基苷类、哌拉西林、三代头孢菌素耐药.结论 RAPD技术为产气肠杆菌分子流行病学研究提供了简便、可靠的手段,菌株的耐药情况可能与标本采集之前抗菌药物的应用有关.     

Outbreak of Enterobacter aerogenes in paediatric unit

Within the framework of breast milk control the hygiene laboratory of Brest hospital isolates, on 3 January 1996 a strain of Enterobacter aerogenes secretory of cephalosporinase in the breast milk of a mother whose child was hospitalized in neonatalogy. On 15 April 1996 a new strain of E. aerogenes is isolated from another mother's breast milk. Until 18 August 1997, 21 samples of breast milk were tested positive to this bacteria. During the same period, E. aerogenes was isolated in 26 children under 1 year of age, 11 of which were infected and 15 colonized. The breast milk did not correspond to those of the mothers of the infected or colonized children. All the strains presented the same antibioresistance. The pulsed-field gel electrophoresis showed that the children's strains, those colonized or infected as well as those isolated in breast milk had the same restriction profile. The epidemiological study concerned the biberonnery-lactarium. The biberonnery's staff is the same as the staff of the lactarium. A portage was searched for among the members of the staff of these units, but without success. The search for E. aerogenes in the environment and in baby-food, others than breast milk was negative. Finally, we did not find any source for these contagions. The only hypothesis we have retained is that of a common source from the biberonnery-lactarium, but without being able to bring any proof to it. Following this epidemic, we have revised all the working modalities and practices with the staff of the biberonnery-lactarium.     

2008-2010年产气肠杆菌分布特征与耐药性分析

目的分析2008-2010年产气肠杆菌分离株的临床分布及耐药性特点,为临床医师诊断和治疗提供依据。方法对2008-2010年住院患者各类标本分离到的产气肠杆菌,进行标本分布和耐药性回顾性统计分析。结果 3年内共分离出产气肠杆菌570株,主要来源于痰334株,占58.6%、尿液121株,占21.2%和血液32株,占5.6%,主要分布在呼吸内科220株,占38.6%、ICU 174株,占30.5%和神经外科42株,占7.4%;药敏结果显示,对氨苄西林、头孢噻肟、头孢西丁、头孢唑林、头孢呋辛酯及头孢呋辛钠耐药率均>50.0%,对阿米卡星、庆大霉素、亚胺培南和美罗培南有较好的敏感性。结论产气肠杆菌多为多药耐药,临床医师应根据药敏结果合理选择抗菌药物,以延缓产气肠杆菌耐药性的产生。     

DNA analysis of nosocomial infection by Enterobacter aerogenes in three cases of septicaemia in Japan

Ceftazidime-resistant Enterobacter aerogenes was isolated from blood cultures of three patients with fever. DNA analysis using pulsed-field gel electrophoresis and ribosomal RNA gene restriction digest pattern analysis revealed that the strains were clonally similar to each other with a 79.3-96.0% homology. The same strain of E. aerogenes was isolated from a three-way stopcock connected to the indwelling catheter in one of the patients at a concentration of 45 cfu/mL. A similar strain was also isolated from the urine of one other patient on the same floor. The data suggest that E. aerogenes caused septicaemia via low bacterial contamination of a three-way stopcock in a peripheral drip intravenous infusion system in at least one patient, and that the outbreak of E. aerogenes infections was due to clonally-related strains.     

MALDiI Botyper与API20E对克罗诺杆菌(阪崎肠杆菌)的鉴定结果比较

目的:评价MALDI-TOF MS Biotyper鉴定克罗诺杆菌的效果。方法:应用MALDI-TOF MS Biotyper与API20E分别对32株克罗诺杆菌(28株分离株,4株参考菌株)与相近菌株阴沟肠杆菌、产气肠杆菌进行鉴定,并对鉴定结果分析比较。结果:MALDI-TOF MS Biotyper2.0将32株克罗诺杆菌鉴定到种、属水平分别为56.2%和37.5%;API20E为75%、21.9%。3株菌未获得鉴定结果,其余29株菌的鉴定结果相符。结论:MALDI-TOF MS Biotyper作为一种新的细菌鉴定手段,可用于克罗诺杆菌的鉴定。     

ICU多重耐药鲍曼不动杆菌医院感染的同源性分析 FREE

目的对某院重症监护室（ICU）流行的多重耐药鲍曼不动杆菌感染进行同源性分析。方法收集该ICU鲍曼不动杆菌感染流行期间住院患者标本中分离的9株以及环境中分离的24株鲍曼不动杆菌,采用基因外重复回文序列聚合酶链反应（REP PCR）技术对其进行基因分析,建立DNA指纹图谱;同时应用K B纸片扩散法进行药敏试验。结果9株临床分离的鲍曼不动杆菌共分为4个基因型,其中E1和E2型分别有4株和3株,E3和E4型各1株;环境样本分离的24株中,17株属E1型。药敏结果显示,临床分离株均为多重耐药株,环境分离株中19株为多重耐药株。结论此次ICU多重耐药鲍曼不动杆菌感染的流行主要是由E1和E2基因型在患者之间的相互传播所致,同时患者所处环境也被明显污染。     

医院内、外感染大肠埃希菌、肺炎克雷伯菌药物敏感性分析

目的 分析比较天津市临床分析的大肠埃希菌、肺炎克雷伯菌对常用抗生素的耐药情况。方法 搜集天津市8所大型综合医院2001年8月～2002年3月临床分析的421株大肠埃希菌和418株肺炎克雷伯菌，进行药物敏感性测定，同时判断菌株来源是否为医院感染的患者。结果 医院感染株对绝大部分抗生素的耐药率都高于社区感染的菌株，其结果有统计学意义，医院感染株ESBLs产生比例也高于社区感染株，其结果存在统计学差异，亚胺培南、阿米卡星、头孢他啶对上述两菌仍有良好的抗菌活性；对喹诺酮类、环丙沙星耐药率，大肠埃希菌医院内、外分别为71．9％和61．1％，对肺炎克雷伯分别为32．2％和21．8％，两者之间无统计学意义}大肠埃希菌对庆大霉素耐药率医院内、外分别为60．3％和48．1％，两者之间无统计学意义。结论 医院感染分离株耐药率高于医院外分离株，应引起经验性使用抗生素的注意，对环丙沙星和庆大霉素的耐药可能与环境因素相关。