深圳市腹泻患者、禽源和牛源空肠弯曲菌的脉冲场凝胶电泳分析

目的 对深圳市禽源、牛源空肠弯曲菌进行脉冲场凝胶电泳,与相同时期和地区腹泻患者分离的空肠弯曲菌比较,寻找空肠弯曲菌传播的证据。方法 对深圳市2016年3—11月分离的不同来源空肠弯曲菌进行复苏、鉴定和脉冲场凝胶电泳,应用BioNumerics软件进行聚类分析。结果 共收集到空肠弯曲菌126株,其中腹泻患者来源22株、禽源44株、牛源60株。除3株不能分型外,其他123株菌成功获得PFGE图谱。不同来源空肠弯曲菌呈现不同的基因特征：人源菌株PFGE带型高度多态化,未发现集中型别;P1是禽源空肠弯曲菌的主要型别;牛源菌株呈现多型别分布,主要型别有C1~C6。综合分析发现,有3个型别（T1、T2和T3）同时包含患者和禽牛来源的菌株。T1型别有12株菌,分别来自患者（3株）、禽类（6株）和牛（3株）,T2型别包含5株菌,来自患者（1株）、禽类（2株）和牛（2株）;T3型别包含7株菌,仅来自患者（1株）和牛（6株）。结论 本研究发现3个空肠弯曲菌型别（T1,T2和T3）同时包含腹泻患者和禽牛来源菌株,为空肠弯曲菌的溯源提供证据。T1可能是深圳市空肠弯曲菌的主要流行型别,在腹泻患者、禽源、牛源菌株中均有分布。     

深圳市龙岗区空肠弯曲菌的流行状况及分子分型

目的了解并分析深圳市龙岗区腹泻患者粪便、禽肉类等样品中空肠弯曲菌的流行状况及同源性。方法对2016年5—12月深圳市龙岗区某医院腹泻患者粪便或肛拭子样品和来自养鸡场、农贸市场、超市等地的禽畜类等样品进行空肠弯曲菌分离培养,菌株经镜检和生化鉴定后再使用脉冲场凝胶电泳(pulsed field gel electrophoresis,PFGE)对其进行全基因组分子分型。最后应用Bio Numerics软件进行聚类分析。结果 41份腹泻患者样品分离出5株空肠弯曲菌,分离率为12.2%,全部阳性样品均来自11岁以下儿童。53份来自食品和外环境样品分离出14株空肠弯曲菌,分离率为26.4%,其中来自农贸市场的分离率为57.1%(8/14),来自不同超市样品空肠弯曲菌的分离率为11.1%(4/36)。18株菌呈现15种PFGE带型,其中来自市场1的3株菌株带型完全一致,且与病例1只有一条带的差异;来自市场2与病例5的带型完全一致且与病例4的带型只有一条带的差异。结论深圳市龙岗区腹泻患者空肠弯曲菌感染率较高,感染可能是由于食用了来自市场未煮熟的食物或接触了来自市场被空肠弯曲菌污染的食物,农贸市场存在空肠弯曲菌的交叉污染,该地区空肠弯曲菌呈现多样性。     

广东省东莞市脑膜炎奈瑟菌多位点序列分型研究

目的 对东莞市2004—2017年分离的41株脑膜炎奈瑟菌（Neisseria meningitidis,Nm）进行基因分型研究,了解菌株间的遗传进化关系。方法 采用多位点序列分型（MLST）技术、进化分析软件BioNumerics 7.5及聚类分析软件eBURST V3对菌株进行核酸序列分析。结果 41株脑膜炎奈瑟菌分为A、B、C、W135四个群,其中1株A群、9株B群、23株C群、8株W135群。共有11个不同STs,分别属于ST-4821、ST-11、ST-5、ST-41/44克隆群及4个无序列分类（UA）,另有1株B群及1株C群菌株无法得到ST型。其中ST-4821 Complex及ST-11 Complex为主要克隆群,分别占61.54%、23.08%。不同血清群其STs/ST-Complex 有明显不同：C群菌株以ST-4821 Complex为主,有 ST-4821、ST-4831、ST-4833、ST-5798型,其中ST-4821型有3种基因序列;W135群全为ST-11 Complex,有ST-11和ST-5412型,ST-11集中在2015年分离出的菌株,均同源;A群仅有1株ST-5型;B群较分散。eBURST V3 聚类分析发现,东莞市ST-11 Complex基因型相对稳定,ST-4821Complex 基因型已具遗传多样性。结论 东莞市Nm 分子型具有基因多样性,以C群（ST-4821/ST-4821 Complex）和W135群（ST-11/ST-11 Complex）两大克隆群占绝对优势,B 群呈分散状态出现在不同的ST克隆群中,可能不同血清群之间已产生荚膜转换,提示B群出现基因重组进化特征。     

广东省茂名市2017—2018年空肠弯曲菌食品分离株病原特征

目的 采集2017—2018年茂名市禽类和畜类食品（仅宰杀切割）,了解空肠弯曲菌携带率,分析其病原学特征。方法 对茂名市禽类和畜类食品（仅宰杀切割）监测过程中分离的空肠弯曲菌进行了抗生素敏感性检测、耐药基因检测和全基因组测序,并基于全基因测序进行遗传进化分析。结果 2017—2018年共检出空肠弯曲菌食品分离株14株,对链霉素、环丙沙星、克林霉素、萘啶酸、阿奇霉素、强力霉素、四环素等抗生素高度耐药,携带着多种耐药基因;基于全基因组的遗传进化分析显示,茂名市检出的12株空肠弯曲菌分离株处在不同进化分支上,显示出多样遗传性。结论 在茂名地区,家禽和畜牧类食品的空肠弯曲菌感染率很高,具有多种抗药性,对畜牧农场和饲料中这种细菌抗药性的监测需要加强,以便为有效防治空肠弯曲菌引起的相关疾病提供参考。     

健康人肠道大肠埃希菌耐药性与质粒图谱的研究

目的 研究深圳市健康人肠道大肠埃希菌携带的质粒与其耐药性之间的关系.方法 分离健康人肠道大肠埃希菌,K-B法测定细菌对16种抗菌素的耐药性,分析细菌的质粒图谱,对耐药菌株进行质粒分子分型.结果 健康人肠道大肠埃希菌对四环素、萘啶酸、磺胺甲基异恶唑、氨苄西林、复方新诺明和链霉素的耐药率分别为63.33%、49.33%、40.67%、38.67%、35.33%、35.33%,全部菌株对头孢美唑和氨曲南敏感.122株菌(81.33%)耐一种以上抗菌素,88株菌(58.67%)耐2种以上抗菌素,44株菌(29.33%)耐5种以上抗菌素,2株菌耐10种抗菌素.结论 深圳市健康人肠道大肠埃希菌耐药性较严重,其耐药性与所携带质粒的数量和大小并无直接联系.     

深圳市市售家禽空肠弯曲菌带菌状况调查

目的了解深圳市当前三鸟市场鸡、鸭、鹅的空肠弯曲菌带菌情况,为进一步开展食品安全性研究,制定防控食源性空腑弯曲菌病的措施提供科学依据。方法从三鸟批发市场采取三鸟肛拭标本,依据GB/T4789．19—2003方法进行细菌检验。结果50份鸡肛拭子共检出空肠弯曲菌20株,阳性率为40％;20份鸭肛拭子共检出空肠弯曲菌2株,阳性率为10％;30份鹅肛拭子共检出空肠弯曲菌6株,阳性率为20％。检出的空肠弯曲菌均为空肠亚种。结论深圳市活禽空腑弯曲菌感染或带菌率较高,如果在销售或加工过程中卫生质量不良,会对消费者的健康构成潜在威胁。     

深圳市肉类食品空肠弯曲菌的污染情况调查

目的了解我市常见肉类食品中空肠弯曲菌的污染状况,为控制和预防空肠弯曲菌食物中毒提供科学依据。方法在食品污监测点随机抽检肉类食品样品117份,用传统国标法和荧光PCR法进行检测。结果从117份肉类食品中检出4份空肠弯曲菌,阳性检出率为3.4%。结论深圳市肉类食品中存在空肠弯曲菌的污染,如果加工、销售不当,及监督不严,会对群众健康构成潜在威胁。     

多重PCR技术对南通市空肠弯曲菌监测结果分析

目的 ：了解南通市不同鸡群、鸡肉、人群及环境中空肠弯曲菌的分布状况。方法：采用多重PCR法对相关鸡的样品、农贸市场环境样品、腹泻患者粪便及健康体检人员肛拭子等进行空肠弯曲菌检测。结果：119份成年鸡肛拭子、124份苗鸡粪便和56份鸡养殖场环境样品分别检出38份、9份和5份空肠弯曲菌阳性,阳性率分别为31.93%、7.26%和8.93%;162份新鲜鸡肉、178份冷冻鸡肉和57份农贸市场环境样品分别检出28份、2份和4份空肠弯曲菌阳性,阳性率分别为17.28%、1.12%和7.02%;418份腹泻患者粪便,9份检出空肠弯曲菌,阳性率为2.15%;857份健康体检人群的肛拭子未检出空肠弯曲菌。结论：在除健康体检人群肛拭子外的7大类样品中均检出空肠弯曲菌,提示南通市存在空肠弯曲菌病的流行隐患,应采取措施对该病进行防控。     

The identification and antimicrobial susceptibility of anaerobic bacteria from pneumonic cattle lungs

One hundred and forty-four lungs obtained postmortem from cattle with pneumonia were cultured for anaerobic bacteria. Forty-five lungs yielded 73 anaerobic isolates belonging to 20 species. The number of isolations of anaerobes from acute fibrinous or suppurative bronchopneumonias (32.5%) was slightly lower than from similar chronic bronchopneumonias (36.5%). Anaerobes were not recovered from 15 lungs showing macroscopic changes not of bacterial origin, nor from 13 healthy lungs. The predominant genera isolated were Bacteroides, Peptococcus, Fusobacterium and Clostridium. The most common species were P. indolicus (15 isolates), B. asaccharolyticus (nine), F. necrophorum (six), C. perfringens (four) and B. fragilis (four). There was a significant correlation between the presence of Corynebacterium pyogenes (p less than 0.001) or Escherichia coli (p less than 0.01) and the presence of anaerobes in the lungs. The isolated anaerobic bacteria were generally susceptible to ampicillin, penicillin G, cefoxitin, cephalothin, clindamycin, chloramphenicol, erythromycin, tetracycline and metronidazole. The B. fragilis and C. perfringens isolates showed multiple antibiotic resistance, and five P. indolicus isolates were resistant to tetracycline.     

揭阳地区妊娠期妇女定植无乳链球菌分子流行特征及耐药特点

目的 了解揭阳地区妊娠期妇女无乳链球菌的分子流行特征和耐药特征,为其引起感染的防控提供依据。方法收集揭阳地区妊娠35~37周妇女的阴道直肠拭子,对分离到的无乳链球菌进行多位点序列分型（multilocus sequence type, MLST）、分子血清分型、进行药敏试验并检测红霉素和克林霉素耐药基因（ermA、ermB、ermA/E和linB基因）。结果无乳链球菌检出率为9.6%（103/1 076）,共发现21个序列型（sequence type, ST）,来源于8个克隆群(clonal complexes,CCs),CC103占16.6%。共检出5个血清型,以Ⅲ（49.5%）、Ia（24.3%）和Ib（12.6%）为主。红霉素、克林霉素耐药率及多重耐药率分别为：71.8%、60.2%和62.1%。红霉素耐药菌均检出耐药基因,ermA、ermB和mefA/E阳性率为16.2%、83.8%和25.7%;linB基因阳性率为54.8%。共检出cMLSB、iMLSB和M型等3种红霉素耐药表型,分别占73.0%、8.1%和18.9%。结论揭阳地区的定植无乳链球菌具有较高的遗传多样性,其多重耐药率高,红霉素耐药以ermB基因介导的cMLSB型为主,部分克林霉素耐药由linB基因介导。CC103已成为该地区流行的主要CC之一;ST17/血清学Ⅲ型为该地区流行的主要定植菌株之一。      

儿童中空肠弯曲菌感染情况的调查

本文报道了成都市及郊区农村529名9岁以下儿童和腹泻病儿室肠弯曲菌感染情况。城乡学龄前儿童的带菌率分别为0.6％和6.5％,二者差异显著(P<0.005)。腹泻病儿空肠弯曲菌阳性率为5.3％,不同年龄组中阳性率有显著差异(P<0.025)。9例空肠弯曲菌肠炎均是2岁以下婴幼儿。63名家庭成员中成人未分离出空肠弯曲菌。结果证实成都市城乡儿童中存在空肠弯曲菌感染。     

DNA fingerprinting of methicillin-resistant Staphylococcus aureus (MRSA) by pulsed-field gel electrophoresis (PFGE) in a teaching hospital in Malaysia

Methicillin-resistant Staphylococcus aureus (MRSA) has been prevalent in our hospital over the last three years. Differentiation among MRSA strains by DNA typing in addition to antibiotic resistance pattern surveillance is crucial in order to implement infection control measures. The aim of this study was to characterize MRSA isolates from patients admitted to Hospital Universiti Kebangsaan Malaysia (HUKM) by phenotypic (analyses of antibiotic susceptibility pattern) and genotypic (PFGE) techniques to determine the genetic relatedness of the MRSA involved and to identify endemic clonal profiles of MRSA circulating in HUKM. Seventy one MRSA strains collected between January to March 2000 from patients from various wards in HUKM were tested for antimicrobial resistance and typed by pulsed-field gel electrophoresis (PFGE). Four major types of PFGE patterns were identified (A, B, C and D) among MRSA strains. Two predominant PFGE types were recognised, Type A (59.2%) and Type B (33.8%). Most of these strains were isolated from ICU, Surgical wards and Medical wards. MRSA strains with different PFGE patterns appeared to be widespread among wards. Strains with the same antibiotype could be of different PFGE types. Most of isolates were resistant to ciprofloxacin, erythromycin, gentamicin and penicillin. One isolate with a unique PFGE pattern Type D and susceptible to gentamicin was identified as a different clone. Some isolates obtained from the same patient showed different PFGE subtypes suggesting that these patients were infected/colonized with multiple MRSA strains. PFGE analysis suggests that MRSA strains with different PFGE types was propagated within our hospital. The relationship between antibiotic susceptibility and PFGE patterns was independent. The ability of PFGE technique in differentiating our MRSA strains make it a method of choice for investigating the source, transmission and spread of nosocomial MRSA infection, and thus an appropriate control programme can be implemented to prevent the spread of MRSA infection.     

Molecular Characteristics of Neisseria meningitidis Isolated during an Outbreak in a Jail: Associatition with the Spread and Distributition of ST-4821 Complex Serogroup C Cltione in China

Objective To characterize the meningococcal strains isolated from cases and close contacts with meningococcal disease associated with an outbreak in a jail in May 2010 by investigating the national distribution of hyperinvasive ST-4821 serogroup C clone associated with this outbreak. Methods The cases were described based on the clinical symptoms and laboratory results. Pharyngeal swabs were cultured for N. meningitidis from men in the jail. Meningococcal isolates were identified by serogrouping, pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST), respectively. Four hundred and sixteen serogroup C N. meningitidis strains were collected from 27 provinces between 2003 and 2010 for a nationwide survey and analyzed by PFGE and MLST. Results Three persons in a jail system were infected with invasive N. meningitidis serogroup C. All isolates tested had matching PFGE patterns and belonged to the multilocus sequence type (ST) 4821 clonal complex. All 47 N. meningitidis strains were identified from the pharyngeal swabs of 166 peoples in the jail, and 26 of them belonged to ST-4821 serogroup C clone, and 90.14% (375/416) serogroup C strains identified in the nationwide survey belonged to the ST-4821 complex. The ST-4821 serogroup C clone was spread nationwide, distributed in 24 provinces, especially in eastern provinces between 2003 and 2010. Conclusion Endemic transmission and carriage rate of ST-4821 serogroup C clone are high in this jail system. The ST-4821 serogroup C clone is spreading in China and nationwide distributed despite the existence of some effective vaccines.     

耐碳青霉烯类肺炎克雷伯菌的分布与耐药性分析

目的 了解耐碳青霉烯类肺炎克雷伯菌（CRKP）的分布特点及其耐药性,为指导临床合理使用抗菌药物提供依据。方法 收集2014年1月至2017年12月临床分离的CRKP菌株,采用自动化仪器法和纸片扩散法（K-B法）对上述菌株进行药物敏感性试验,药物敏感性结果严格按照美国临床和实验室标准化协会（CLSI）和美国食品药品管理局（FDA）标准判定。采用WHONET软件和SPSS 20.0软件对数据进行统计分析。结果 共收集临床分离CRKP菌株403株,主要标本来源为痰/支气管肺泡灌洗液（169株,占41.9%）。CRKP首次分离标本来源不同,后续CRKP血流感染的发生率也不同,差异有统计学意义（P<0.05）。CRKP来源科室位列前3位的分别为烧伤重症监护病房（30.0%,121/403）、消化科（8.4%,34/403）和急诊重症监护病房（7.2%,29/403）。药物敏感性试验结果显示CRKP除对替加环素和磷霉素耐药率较低外,对其余抗生素的耐药率均>60.0%。结论 CRKP对多数常用抗生素呈现高度耐药。应加强对CRKP的耐药性监测,尤其是烧伤重症监护病房等重点科室,并采取有效措施预防和控制CRKP的传播。     

嗜麦芽窄食单胞菌医院感染特点及耐药性分析

目的分析近2年我院发生的嗜麦芽窄食单胞菌(SMA)医院感染的特点及耐药性,为控制感染和临床合理使用抗菌药物提供依据。方法采用美国临床实验室标准化委员会(NCCLS)推荐的纸片扩散法,检测从40例感染患者中分离的50株SMA对24种抗生素的耐药情况,通过脉冲场凝胶电泳(PFGE)全DNA指纹技术对菌株进行分型。结果 SMA感染主要发生在下呼吸道,50岁以上的患者居多,且多数为混合感染。SMA对头孢吡肟/舒巴坦、加替沙星、左氧氟沙星、氧氟沙星、敏感性高,而对多数抗菌药物耐药,对头孢曲松、头孢呋辛、头孢西丁的耐药率达到了100.0%,对亚胺培南、氨曲南、四环素、哌拉西林和庆大霉素耐药率分别为92.3%、88.9%、82.4%、75.0%和70.0%。多数SMA(17/21)没有同源性,仅一对同源菌株来自同一病房,另一对同源菌株来自医院的不同病房。结论患者被医院环境中自然存在的SMA定植可能是SMA基因组的多样性和低同源性的原因。头孢吡肟/舒巴坦、加替沙星、左氧氟沙星、氧氟沙星、头孢哌酮/舒巴坦是治疗SMA感染的有效药物。     

Antimicrobial susceptibility of Salmonella isolates from the broiler chicken industry in Ontario.

Antibacterial drug resistance among 219 salmonella isolates recovered during 1974 from poultry and poultry environments at the various production stages of broiler chickens in three integrated Ontario companies are recorded. All isolates were susceptible to ampicillin, trimethroprim-sulfamethoxazole complex, furazolidone, cephaloridine and amoxicillin. A relative increase in resistance to tetracycline and streptomycin with an accompanying decrease in resistance to triple sulfa compound was recorded when compared to a previous investigation of avian salmonella isolates in Ontario. The percentage and patterns of antimicrobial resistance were comparable at the various stages of production. Resistance to tetracycline and streptomycin was the most common pattern found among both Salmonella typhimurium and other serotypes. A notably high prevalence of resistance was found among Salmonella enteritidis isolates including some isolates with R factors for chloramphenicol resistance. This latter finding is of particular concern because of the high prevalence of this serotype in poultry and in human salmonellosis.     

Antimicrobial resistance, genotypic characterization and pulsed-field gel electrophoresis typing of extended spectrum β-lactamases-producing clinical Escherichia coli strains in Macao, China

Background  The rise of the production of CTX-M class extended spectrum β-lactamases (ESBLs) has been well documented in traveling countries but no data are found for Macao, an international travel city. The objectives of this study were to identify the antimicrobial resistance pattern, and determine the prevalence, genotype and clonal relationship of ESBLs in 209 clinical Escherichia coli strains from Macao, China.

Methods  Antimicrobial susceptibility test was performed to determine the resistance patterns of the isolates using the disk diffusion method with 17 antimicrobial agents. Phenotypic detection was screened and confirmed according to the Clinical and Laboratory Standards Institute. Genotypic characterization was detected by isoelectric focusing analysis, polymerase chain reaction and sequencing. The clonal relationship between the different ESBL isolates was studied by pulsed-field gel electrophoresis (PFGE).

Results  Imipenem and meropenem exhibited 100% susceptible among 209 strains. Overall, 82.3%, 67.3%, 52.9%, 51.2% and 51.0% of the isolates displayed resistance to ampicillin, tetracylcline, ciprofloxacin, sulfamethoxazole trimethoprin and gentamycin. The prevalence rate of ESBLs was 30.1%. Antibiotic resistances were found to be significantly higher among the ESBL producing group compared to non-ESBL producing group. We detected CTX-M-14 to be the major genotypic characterization of ESBLs (76.2%). Two strains showed indistinguishable patterns by PFGE.

Conclusions  The prevalence of antimicrobial resistance is alarming high in Macao. Antimicrobial resistance is significantly higher among the ESBL producing group. This study documented CTX-M-14 as the predominant ESBL type. Although indistinguishable pattern was found between two strains, it was too small to decide whether any of the investigated strains was epidemic. Our findings may be also pertinent for other geographic areas undergoing similar travel characteristics to understand the corresponding effects on bacterial populations.

     

神经外科患者脑脊液细菌流行病学和耐药性10年监测

目的 监测神经外科患者脑脊液致病菌流行病学分布及耐药状况.方法 收集北京天坛医院神经外科1997年8月至2006年9月,送检脑脊液标本中分离的致病菌及药敏鉴定结果,统计致病菌分布和抗菌药物敏感率.结果 分离到致病菌970株,其中革兰阳性球菌720株;革兰阴性杆菌250株.排名前6位的致病菌分别为:表皮葡萄球菌(25.4%),金黄色葡萄球菌(9.4%),不动杆菌(6.9%),肠杆菌属(5.0%),铜绿假单胞菌(2.8%),肠球菌属(2.8%).对革兰阴性菌的平均敏感率亚胺培南为94%,阿米卡星为75%,头孢吡肟为59%,头孢他啶为54%.对革兰阳性球菌(葡萄球菌属,肠球菌属)平均敏感率万古霉素为100%,利福平为78.2%,复方磺胺甲嗯唑为65.6%,苯唑西林为16.7%.结论 神经外科患者颅内感染以革兰阳性球菌多见,尤其是表皮葡萄球菌和金黄色葡萄球菌.本组结果可为神经外科手术部位感染的预防和经验性抗菌药物治疗提供基本数据资料.     

空肠弯曲菌脂多糖在格林巴利综合征发病中的分子模拟机制研究

目的：分析空肠弯曲菌脂多糖（LPS）与格林巴利综合征（GBS）患者神经组织之间是否存在分子模拟现象以及探讨空肠弯曲菌LPS在GBS发病中的作用机制。方法：首先从GBS患者粪便中分离培养出空肠弯曲菌，经鉴定后提取其LPS，用空肠弯曲菌LPS制备出GBS动物模型（实验性变态反应性神经炎），最后利用噬菌体肽库筛选技术分析空肠弯曲菌和GBS患者神经组织之间是否存在相似性抗原表位。结果：空肠弯曲菌LPS、牛髓鞘碱性蛋白以及GBS患者外周神经成分之间存在相似抗原表位。结论：空肠弯曲菌LPS和GBS患者外周神经神经节苷脂成分之间存在分子模拟现象，GBS的发病是由于机体针对感染原的免疫应答通过交叉反应导致外周神经组织损伤所致。