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1.
目的了解我院耐万古霉素肠球菌(VRE)的耐药表型、基因型及流行情况。方法用K-B纸片扩散法检测临床分离肠球菌的药物敏感性,E-test法检测VRE对万古霉素的最低抑菌浓度(MIC);PCR检测vanA、vanB、vanC1和vanC2-3基因型;脉冲场凝胶电泳(PFGE)分析VRE同源性。结果 73株肠球菌中检出3株万古霉素耐药屎肠球菌,检出率为4.1%;3株屎肠球菌对万古霉素和替考拉宁均耐药,但对利奈唑胺敏感;基因型检测显示3株屎肠球菌均为vanA型,PFGE结果显示该3株VRE不属于同一型别。结论我院住院患者中已出现VRE,应加强医院感染控制,以阻止VRE菌株在院内的传播和流行。  相似文献   

2.
目的研究万古霉素耐药肠球菌(VRE)的耐药表型和基因特性。方法采用浓度梯度法(E-test)测定VRE对万古霉素(VA)、替考拉宁(TP)的耐药表型;采用聚合酶链反应检测vanA、vanB、vanC1、vanC2、vanC3基因,并对van基因产物进行测序。结果万古霉素耐药基因检测结果:VRE经PCR扩增,均获得vanA基因阳性片段。未检测到vanB、vanCl及vanC2/3基因。结论万古霉素耐药肠球菌的耐药表型与耐药基因型一致,菌株之间有较高的同源性。住院患者肠道中VRE携带率高,是医院感染的危险因素。  相似文献   

3.
目的了解中山大学附属第一医院临床分离的耐万古霉素肠球菌(VRE)的基因型和同源性,为本地区VRE的感染治疗和预防控制提依据。方法收集临床分离的VRE,E-Test法确定万古霉素、替考拉宁和利奈唑胺的最低抑菌浓度(MIC),多重PCR法检测万古霉素耐药基因,脉冲场凝胶电泳(PFGE)检测菌株的同源性。结果共收集到8株VRE菌株,均为屎肠球菌,分离自腹腔引流液。8株VRE均对万古霉素高度耐药(MIC≥256mg/L),对替考拉宁中介或耐药,对利奈唑胺、替加环素和四环素敏感,耐药基因型均为VanA;PFGE分型分为A、B两个克隆,其中7株为A克隆,1株为B克隆。结论中山大学附属第一医院VRE菌株均携带VanA基因,且多重耐药,在院内有小范围的流行,但非单一克隆流行。  相似文献   

4.
对万古霉素耐药的11株肠球菌的药敏表型及基因检测   总被引:11,自引:0,他引:11  
目的 检测11株耐万古霉素肠球菌(VRE)的耐药表型、基因型以及多耐基因。方法 采用纸片扩散法、微量稀释法、自动化仪器、浓度梯度法测定11株VRE对万古霉素(Van)、替考拉宁(Tec)的耐药表型,微量稀释法测定11株VRE对10种抗菌药物的最低抑菌浓度;多重聚合酶链反应检测vanA、vanB、vanC1、vanC2并对van基因产物进行测序,聚合酶链反应检测TEM、tetM、ermB、aac(6′)/aph(2″)、ant(6)-Ⅰ、aph(3′)-Ⅲ基因。结果 不同药敏方法测得11株VRE对Van、Tec的药敏结果有差异;11株VRE对红霉素(9/11)、环丙沙星(7/11)、左氧氟沙星(7/11)、利福平(8/11)、氯霉素(7/11)耐药程度较高,高水平庆大霉素耐药株(HLGR)、高水平链霉素耐药株(HLSR)分别占10/11和9/11。11株VRE检出1株VanA、4株VanB、5株VanC1,1株VanC2,基因型和表型一致;耐药基因TEM(8/11)、tetM(6/11)、ermB(7/11)、aac(6′)/印h(2″)(7/11)、ant(6)-Ⅰ(5/11)、aph(3′)-Ⅲ(9/11)检出率高。结论 VRE确证试验以及准确检测其MIC值是筛查VRE不漏诊的可靠方法;van基因的检测是从分子水平确定VRE准确特异的方法;耐药基因的高检出率体现了VRE复杂的耐药机制。  相似文献   

5.
目的明确万古霉素耐药肠球菌(vancomycin resistant enterococci,VRE)耐药基因型别及耐药性,指导临床用药。方法收集北京中日友好医院2016年10月至2017年10月临床分离的17株VRE,Vitek 2 Compact全自动细菌鉴定及药敏分析系统检测其对临床常用14种抗菌药物的敏感性,E-test法确证其对万古霉素和替考拉宁的药物敏感性;PCR法检测17株VRE的耐药基因vanA、vanB、vanC1、vanC2/3,并经测序验证。结果 17株VRE均为耐万古霉素屎肠球菌,均对环丙沙星、左氧氟沙星、莫西沙星、青霉素100%耐药,对利奈唑胺、替加环素、奎奴普丁/达福普汀等敏感;其耐药基因型均为vanA型,其中有4株vanB表型-vanA基因型。结论所收集的VRE均对万古霉素高水平耐药,耐药型均为vanA型,应加强临床分离株的耐药监控,合理使用抗菌药物。  相似文献   

6.
耐万古霉素肠球菌的基因检测   总被引:1,自引:0,他引:1  
目的 调查上海华山医院2007-2009年间VRE的分离率,并对耐药菌株的分子特性进行研究,为本地区VRE的预防和控制提供有价值的信息.方法 通过琼脂平板稀释法(ADSP)从临床鉴定的890株肠球菌中筛选VRE菌株,并通过微量肉汤稀释实验测其对万古霉素及替考拉宁的MIC;采用PCR及测序方法检测万古霉素耐药基因以及可能毒力基因esp,hyl;运用MLST对VRE进行克隆分型并通过PFGE分型技术进行验证.结果 ADSP法及微量肉汤稀释实验共筛选出13株VRE菌株.其中6株VRE(2007-2008年)只对万古霉素耐药,但对于替考拉宁敏感(万古霉素MIC64~256μg/ml);耐药基因PCR产物测序结果提示这6株VRE均携带同一种可能导致万古霉素耐药的新型基因,该基因序列与已报道的耐药基因均不同;MLST及PFGE分型提示其属于不同型别.另外7株VRE(2009年1-7月)对万古霉素和替考拉宁的MIC结果分别为32~64μg/ml和16~32 μg/ml,耐药基因检测均为vanA.MLST分型结果提示13株VRE共分为4个不同的ST型,其中11株均属克隆复合型CC-17.13株VRE毒力基因esp和hyl的阳性率分别为69.2%和30.8%.结论 上海华山医院VRE克隆分型以CC17为主,同时发现上海华山医院存在一种可能导致万古霉素耐药的新型基因介导的VRE,该新基因的功能和定位尚待进一步研究.  相似文献   

7.
耐万古霉素肠球菌表型检测及基因分型   总被引:11,自引:1,他引:11  
目的 研究对万古霉素耐药或中介的肠球菌株的表型和基因型,以了解本院耐万古霉素肠球菌(VRE)的流行状况,指导临床合理用药。方法 收集200株临床分离的肠球菌株,用琼脂筛选法筛选VRE,并分别用E test和多重PCR检测和分析对万古霉素耐药或中介肠球菌株的表型和基因型。结果 共检出10株对万古霉素耐药或中介的肠球菌株,其中5株为天然耐万古霉素肠球菌。基因型分析的结果为1株van A型,4株van C1型,3株van C2型,2株基因型不明。结论 已发现5株VRE(1株VAN A型),提示临床上须合理使用抗生素,以防止VRE等多重耐药细菌的爆发流行。  相似文献   

8.
目的研究肠球菌的耐药率及耐万古霉素肠球菌(VRE)的耐药表型和基因型。方法按照美国临床和实验室标准化研究所(CLSI)2009年推荐的微量稀释法进行临床分离肠球菌对各类药物的最小抑菌浓度(MIC)检测,VRE进一步用E-test药敏试验确认;PCR法检测VRE的耐药基因。结果 2010年7月至2011年11月沈阳军区总医院共检出粪肠球菌95株,屎肠球菌163株。粪肠球菌对万古霉素、替考拉宁保持较高敏感度,对氨苄西林、青霉素、呋喃妥因三种抗菌药物敏感度也在65%以上,对其他抗菌药物敏感度低,统计期内未检出耐万古霉素粪肠球菌菌株。屎肠球菌对多数抗菌药物表现为耐药,对氯霉素敏感率为70%,对万古霉素、替考拉宁敏感度下降,为90.7%。期间检出15株VRE,其耐药表型为多重耐药,PCR扩增结果显示,15株万古霉素耐药屎肠球菌VanA基因扩增均为阳性,产物长度在700~1000bp之间,约783bp,符合预期;VanB、VanC引物扩增均阴性。15株万古霉素耐药屎肠球菌对多数抗菌药物耐药,仅对氯霉素、四环素相对敏感,对万古霉素MIC>256mg/L,对替考拉宁也表现为耐药。结论屎肠球菌耐药性高于粪肠球菌,VRE多为多重耐药,给临床治疗带来困难,医院应加强对其预防监测。  相似文献   

9.
VanB表型-vanA基因型VRE分子特征及遗传背景研究   总被引:1,自引:0,他引:1  
目的 探讨VanB表型-vanA基因型VRE耐药转座子结构、分子特征及遗传背景,并与VanA表型-vanA基因型VRE进行比较分析,以确定基因型与表型不一致的形成机制.方法 收集2008年3月至2009年1月卫生部北京医院临床标本中21株VRE菌株,用Etest法对10种抗生紊进行MIC测定,并通过PCR、序列测定、接合试验、耐药转座子结构、PFGE及MLST进行分子特征和遗传背景研究.结果 21株VRE均为vanA基因型,其中3株菌呈现VanB表型(万古霉素耐药,替考拉宁敏感);21株菌属于9个不同PFGE型,6个不同MIST型;多对引物对转座子的不同区域PCR扩增并进行序列拼接、比对,发现Tn1546结构中vanX、vanY的缺失及ISEfa4的插入与VanB表型-vanA基因型VRE菌株形成相关.结论 VanB表型-vanA基因型VRE菌株在国内较为罕见,Tn1546结构的改变与菌株的基因型与表型不一致相关.  相似文献   

10.
下呼吸道标本MRSA耐药性及分子流行病学研究   总被引:1,自引:0,他引:1  
目的了解下呼吸道标本中MRSA的耐药性及分子流行病学特点。方法采用Kirby-Bauer纸片扩散法,对我院2005年12月至2006年12月下呼吸道标本分离的107株MRSA药敏结果进行分析;采用脉冲场凝胶电泳(PFGE)对其中32株MRSA进行同源性分析。结果107株MRSA对14种抗菌药物的药敏结果显示对万古霉素、替考拉宁和利奈唑胺均敏感;对奎奴普丁-达福普汀和利福平显示较好的敏感性,敏感率分别为93.5%、70.1%;其次为对氯霉素敏感率54.2%;对四环素、庆大霉素、克林霉素和左氧氟沙星等显示高度耐药或全耐药。PFGE分析表明32株MRSA分为4个PFGE组(A~D型),25株为A型,A型又包括A1、A2、和A33个亚型,其中以A1亚型为主,共17株,A2亚型1株,A3亚型7株,B型5株,C型1株,D型1株。结论我院在2005年12月到2006年12月ICU、结核5科有MRSA暴发流行,主要流行株为A1、A3亚型;这些MRSA菌株为多重耐药菌,应引起临床医师及感染控制部门高度重视。  相似文献   

11.
Avoparcin was used as a feed additive in New Zealand broiler production from 1977 until June 2000. We report here on the effects of the usage and discontinuation of avoparcin on the prevalence of vancomycin-resistant enterococci (VRE) in broilers. Eighty-two VRE isolates were recovered from poultry fecal samples between 2000 and mid-2001. VRE isolates were only obtained from broiler farms that were using, or had previously used, avoparcin as a dietary supplement. Of these VRE isolates, 73 (89%) were VanA-type Enterococcus faecalis and nine (11%) were VanA-type Enterococcus faecium. All E. faecalis isolates were found to have an identical or closely related pulsed-field gel electrophoresis (PFGE) pattern of SmaI-digested DNA and were susceptible to both ampicillin and gentamicin. The PFGE patterns of the nine E. faecium isolates were heterogeneous. All VRE contained both the vanA and ermB genes, which, regardless of species or PFGE pattern, resided on the same plasmid. Eighty-seven percent of the VRE isolates also harbored the tet(M) gene, while for 63 and 100%, respectively, of these isolates, the avilamycin and bacitracin MICs were high (>or=256 microg/ml). Five of eight vancomycin-resistant E. faecalis isolates recovered from humans in New Zealand revealed a PFGE pattern identical or closely related to that of the E. faecalis poultry VRE isolates. Molecular characterization of Tn1546-like elements from the VRE showed that identical transposons were present in isolates from poultry and humans. Based on the findings presented here, a clonal lineage of VanA-type E. faecalis dominates in VRE isolated from poultry and humans in New Zealand.  相似文献   

12.
Vancomycin-resistant enterococci (VRE) are endemic in health care settings. These organisms colonize the gastrointestinal tract and can lead to infection which is associated with increased mortality. There is no treatment for VRE colonization. We conducted a randomized, double-blind, placebo-controlled clinical trial to examine the safety and efficacy of administration of the probiotic Lactobacillus rhamnosus GG (LGG) for the reduction or elimination of intestinal colonization by VRE. Colonized adults were randomized to receive LGG or placebo for 14 days. Quantitative stool cultures for LGG and VRE were collected at baseline and days 7, 14, 21, 28, and 56. Day 14 stool samples from some subjects were analyzed by quantitative PCR (qPCR) for LGG. Patients were closely monitored for adverse events. Eleven subjects, of whom 5 received LGG and 6 received placebo, were analyzed. No differences in VRE colony counts were seen at any time points between groups. No decline in colony counts was seen over time in subjects who received LGG. LGG was detected by PCR in all samples tested from subjects who received LGG but was only isolated in culture from 2 of 5 subjects in the LGG group. No treatment-related adverse events were seen. We demonstrated that LGG could be administered safely to patients with comorbidities and is recoverable in some patients'' stool cultures. Concomitant administration of antibiotics may have resulted in an inability to recover viable organisms from stool samples, but LGG DNA could still be detected by qPCR. LGG administration did not affect VRE colonization in this study. (This study was registered at Clinicaltrials.gov under registration no. NCT00756262.)  相似文献   

13.
BACKGROUND: The purpose of this study was to assess the prevalence of vancomycin-resistant enterococci (VRE) in urinary isolates in North America, and the activity of various antibiotics against VRE. MATERIALS AND METHODS: Twenty-eight medical centres in the United States and 10 centres in Canada assessed the prevalence of VRE in urinary isolates in 2002. Each study site was asked to collect up to a maximum of 50 consecutive VRE (Enterococcus faecium, Enterococcus faecalis only) urinary isolates. Susceptibility was determined by NCCLS broth microdilution. The prevalence of vanA and vanB resistance genotypes was determined by multiplex PCR. RESULTS: From the 28 US medical centres, a total of 697 VRE (616 [88.4%] E. faecium and 81 [11.6%] E. faecalis) were received. Approximately 75% of all VRE (E. faecium and E. faecalis) isolates demonstrated a VanA phenotype (resistance to both vancomycin and teicoplanin). PCR detection of vanA and vanB resistance determinants showed that the vanA genotype was present in 584 of 697 (83.8%) VRE isolates, whereas 113 (16.2%) isolates possessed the vanB gene. The most active agents were linezolid, nitrofurantoin and chloramphenicol, with 0.3%, 0.6% and 2.4% resistance, respectively. The majority (77.8%) of vancomycin-resistant E. faecium isolates displayed the VanA phenotype, and 538 of these 616 (87.3%) isolates were PCR-positive for vanA; the vanB genotype was detected in 78 (12.7%) isolates. Resistance was lowest with linezolid, chloramphenicol and nitrofurantoin at 0.3%, 0.3% and 0.5%, respectively. Only three genetically indistinguishable vanA-positive E. faecium were isolated from the 10 Canadian medical centres. CONCLUSION: VRE urinary isolates are common in the United States, are primarily of the vanA genotype and are very susceptible to linezolid, nitrofurantoin and chloramphenicol. In Canada, VRE urinary isolates remain uncommon.  相似文献   

14.
A survey in eight European countries, including 13 hospitals, of vancomycin-resistant enterococci (VRE) in at-risk hospital wards (such as the ICU and the haematology ward) was performed in 2001, and the in vitro susceptibility of the isolates ramoplanin and other drugs was tested. A total of 1314 non-duplicate clinical enterococcal isolates were collected, and 38 (2.9%) were vancomycin resistant: 27 Enterococcus faecium and 11 Enterococcus faecalis; 35 VanA and three VanB phenotypes. Rates of VRE among clinical enterococcal isolates varied between 0 and 1.7% for the participating countries, except the UK (10.4%) and Italy (19.6%). One hundred and twenty-three (3.5%) VRE were found among 3499 stool samples tested for the presence of these organisms: 111 (3.2%) E. faecium and 12 (0.3%) E. faecalis; 114 (3.3%) VanA and nine (0.3%) VanB phenotypes. Rates of intestinal colonization with VRE varied between 0 and 1.2% for the participating countries, except Italy (7.5%) and the UK (32.6%). In vitro susceptibility testing showed that the Italian and UK VRE are multi-resistant (including resistance to ampicillin and high-level resistance to gentamicin and streptomycin), and that ramoplanin was active against all strains of VRE, with an MIC90 of 0.5 mg/L for clinical isolates. Pulsed-field gel electrophoresis showed that the high prevalence of VRE in the Italian and UK centres was related to the monoclonal emergence and spread of three centre-specific clones. This survey suggests that in some centres in Europe, a similar situation may be encountered to that in the USA (monoclonal spread of multi-resistant VRE in at-risk wards).  相似文献   

15.
Surveillance for vancomycin resistant enterococci (VRE) by culture can be labour intensive and time consuming. We have developed a multiplex polymerase chain reaction (MPCR) which can be performed directly on the clinical specimen. The assay allows sensitive detection of enterococci with vanA - and vanB -mediated resistance to vancomycin. DNA was purified from stool and rectal specimens using the XTRAX(TM)DNA Extraction Kit (Gull Labs). Multiplex PCR amplified vanA and vanB targets were detected using a microtiter plate EIA. Two-hundred specimens were tested by routine culture and MPCR. Culture identified 44 VRE isolates and MPCR detected 38 of the 44 culture positives. Multiplex PCR detected three additional positive VRE specimens missed by culture for a sensitivity and specificity of 86.4 and 98.1%, respectively. When the presence of PCR inhibitors was addressed in the six culture positive/MPCR negative specimens, four additional VRE positive specimens were detected. Performing MPCR on the original specimens and on a 1:10 dilution of all specimens to minimize the effect of inhibitors gave a sensitivity and specificity of 95.5 and 98.1%, respectively. Multiplex PCR with confirmation by microtiter plate hybridization could be completed in 8 h compared with 24-48 h required for culture.  相似文献   

16.
To identify whether the incidence of human papillomavirus (HPV) type 18 DNA in adenocarcinoma and adenosquamous carcinoma is attributable to the histological types or geographical differences, the presence of HPV-16 and HPV-18 DNA in carcinoma of the uterine cervix from Japan were studied by in situ hybridization using tritium labeled HPV DNA probes. HPV-18 DNA was detected in 5 of 11 cases (45%) of adenocarcinoma, one case of adenocarcinoma in situ and 2 of 3 cases of adenosquamous carcinoma. In contrast, HPV-16 DNA was detected in 2 of 11 cases (18%) of adenocarcinoma, and 3 of 7 cases (43%) of squamous cell carcinoma. Compared with our previous results (Tase et al. 1988), the present results imply that the prevalence of HPV-18 DNA in carcinoma of the uterine cervix is attributable rather to the histological differences than to the geographical differences.  相似文献   

17.
The prevalence of resistance in enterococci to antibiotics, commonly used for therapy in poultry or as antimicrobial growth promoters (AMGPs), was determined in faecal samples of two chicken populations: broilers in which antibiotic and AMGP use is common and laying-hens with a low antibiotic usage. In addition faecal samples were examined from three human populations: broiler farmers, laying-hen farmers and poultry slaughterers. MICs of an extended panel of antibiotics for a randomly chosen gentamicin- or vancomycin-resistant enterococcal isolate from each faecal specimen were also determined. The prevalence of resistance for all antibiotics tested was higher in broilers than in laying-hens. Resistance in faecal enterococci of broiler farmers was for nearly all antibiotics higher than those observed in laying-hen farmers and poultry slaughterers. The overall resistance in broilers was correlated with the resistance in broiler farmers and in poultry slaughterers. No correlation between the results obtained in the laying-hens with any of the other populations was found. The 27 gentamicin-resistant isolates all showed high-level resistance to gentamicin and two of these isolates, both Enterococcus faecium, were resistant to all antibiotics tested, except vancomycin. The 73 vancomycin-resistant enterococci (VRE) isolated from the five populations belonged to four different species and in all isolates the vanA gene cluster was detected by blot hybridization. The pulsed-field gel electrophoresis (PFGE) patterns of these vancomycin-resistant enterococci were quite heterogeneous, but Enterococcus hirae isolates with the same or a closely related PFGE pattern were isolated at two farms from the broiler farmer and from broilers. Molecular characterization of vanA-containing transposons of these isolates showed that similar transposon types, predominantly found in poultry, were present. Moreover, similar vanA elements were not only found in isolates with the same PFGE pattern but also in other VRE isolated from both humans and chickens. The results of this study suggest transmission of resistance in enterococci from animals to man. For VRE this might be clonal transmission of animal strains, but transposon transfer seems to occur more commonly.  相似文献   

18.
Outbreaks of vancomycin-resistant enterococci (VRE) infection occur sporadically in Japan, and their frequency has been gradually increasing. We experienced a nosocomial outbreak of VRE in two hospitals in the city of Kitakyushu, and the spread of VRE strains was suspected in this area. To examine the prevalence rate of infection and colonization of VRE in Kitakyushu, we screened a total of 24297 clinical samples from patients in hospitals and clinics in Kitakyushu from October through December 2002 for VRE. The isolates screened as positive for VRE accounted for 2.3% (566/24297) of the tested clinical samples. Polymerase chain reaction (PCR) analyses for vanA, vanB, vanC1, and vanC2/3 were performed to confirm the screening test results. Neither vanA nor vanB genes were detected in any isolates. The 265 vanC1-positive isolates were Enterococcus gallinarum, and the 150 vanC2/3-positive isolates were E. casseliflavus. Other Enterococcus species were negative in this PCR-detection test. In this study, the PCR procedure was considered reliable and successful because although neither vanA nor vanB was detected, vanC1 and vanC2/3 were completely detectable. Therefore, we concluded that the regional spread of VRE with vanA and vanB had not occurred in Kitakyushu in 2002. In the near future, the prevalence of VRE with vanA or vanB is likely to increase in Japan, as it has in other countries. We should continue to find and prevent nosocomial outbreaks of infection and colonization by VRE.  相似文献   

19.
At a university hospital in Japan, a total of 15 patients (14 adults and 1 newborn baby) with vancomycinresistant enterococci (VRE) infection or colonization (inf/col) were identified via routine clinical examinations and two nonroutine examinations from January to April 2007. Two case-control studies were conducted to identify the factors related to VRE inf/col. In study 1, the patients with VRE inf/col from ward A (n = 8) were compared with all of the patients without VRE isolates in the same ward, i.e., the controls (n = 26). In study 2, all adult patients with VRE inf/col throughout the hospital (n = 14) were compared with controls randomly selected from among all patients without VRE isolates (n = 45). All the subject cases were found to be infected or colonized with Enterococcus faecium, vanB. All but two of the isolated strains were completely identical according to pulsed field gel electrophoresis. Univariate analysis in study 2 showed several factors, including the isolation of methicillin-resistant Staphylococcus aureus (MRSA) (odds ratio [OR], 8.6; 95% confidence interval [CI], 1.3–53.7) and the use of antibiotics other than anti-MRSA drugs (OR, 33.0; 95% CI, 1.8–587.6) to be risk factors for VRE inf/col. Multivariate logistic regression analysis in study 2 demonstrated associations with VRE inf/col in the use of an ultrasound nebulizer (OR, 5.9; 95% CI, 1.5–22.8) and extended bed rest (OR, 3.8; 95% CI, 1.02–24.5). Although severe infection with VRE did not occur, to avoid the spread of VRE in hospital wards, further staff education should be implemented in regard to the usual standard and contact precautions, and the appropriate selection of antibiotics.  相似文献   

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