广东省腹泻病例非伤寒沙门菌耐药谱和PFGE分型研究

目的 了解广东省腹泻病例非伤寒沙门菌的耐药状况,并对多重耐药菌株进行脉冲场凝胶电泳(PFGE)分型研究.方法 利用血清学方法对2009-2011年广东省腹泻病例分离的非伤寒沙门菌进行分型,并用CLSI( Clinical and Laboratory Standards Institute)推荐的纸片法对分离的沙门菌株进行抗生素敏感性检测,采用PFGE进行分型研究.结果 91.76％ (256/279)的鼠伤寒沙门菌对3种及以上抗生素耐药,40株鼠伤寒沙门菌同时对9种及以上抗生素耐药,其中有3株对全部12种抗生素耐药.96.91％ (94/97)的I4,5,12:i:-沙门菌对3种及以上抗生素耐药,9株14,5,12:i:-沙门菌同时对9种及以上抗生素耐药,其中有1株对全部12种抗生素耐药.47％(47/100)的肠炎沙门菌对3种及以上抗生素耐药,其中1株对9种及以土抗生素耐药.环内沙星的耐药率为4.27％( 27/632),其中,17株为鼠伤寒沙门菌,6株为14,5,12:i:-沙门菌.31.96％( 202/632)的沙门菌对环丙沙星显示为中介敏感性.这些多重耐药的菌株和具有相同耐药谱的菌株PFGE指纹图谱不完全一致,PFGE型别存在明显的遗传多样性.结论 广东省非伤寒沙门菌多重耐药现象严重.多重耐药菌株的PFGE型别多样,存在明显的遗传多样性.继续加强耐药监测和控制抗生素的合理使用刻不容缓.     

伤寒沙门菌PFGE分子分型及耐药性研究

目的对深圳市2004—2011年伤寒沙门菌进行脉冲场凝胶电泳（PFGE）分子分型及耐药性分析,为临床用药和追踪传染源提供依据。方法采用K-B法对42株伤寒沙门菌进行20种抗菌药物敏感性测试,并用PFGE对其进行分子分型。结果42株伤寒沙门菌株对氨苄西林、阿莫西林／克拉维酸、氨苄西林／舒巴坦、头孢噻吩、头孢他啶、头孢曲松、头孢吡肟、头孢西丁、阿米卡星、庆大霉素、卡那霉素、环丙沙星、左旋氧氟沙星、复方新诺明、甲氧苄啶、氯霉素和四环素17种药物的敏感率均超过90％,对萘啶酸耐药率最高达61．5％。42株伤寒沙门菌株可分为SZ0001～SZ0028共28个PFGE型别,其中流行优势型为SZ0023型别。结论结合药物敏感试验结果和PFGE分子分型结果可以判断伤寒疫情的优势株型。     

肠道致病菌PCR检测与鉴定研究

目的 为了实现对腹泻等病原菌的快速、准确检测与鉴定，对引起感染性腹泻的暴发与流行的常见肠道致病菌进行检测与鉴定方法研究。方法 将常规ＰＣＲ与半套式ＰＣＲ及随机引物扩增ＤＮＡ多态性分析（ＲＡＰＤ）等技术相结合，对常见肠道致病菌，如志贺菌、沙门菌和致病性大肠杆菌Ｏ１５７：Ｈ７等进行检测与鉴定。结果 ｕｉｄＡ引物可特异扩增沙门菌、志贺菌及大肠杆菌，而３种特异性引物则只扩增相应的致病菌；第一次ＰＣＲ敏感性     

33例儿童非伤寒沙门菌肠炎临床分析及耐药监测

目的:探讨儿童非伤寒沙门菌肠炎临床特征、血清型及耐药性。方法:对我院2012年11月至2015年11月经粪便培养确诊为非伤寒沙门菌肠炎的33例患儿进行回顾性分析,探讨其临床特征、血清分型、耐药性等。结果:本组病例发病以婴幼儿多见,发病季节多集中在5-10月,所有患儿均有腹泻,且大部分以腹泻起病,其中28例患者伴发热,血清型以肠炎沙门菌、鼠伤寒沙门菌为主(39.39%;36.36%)。美洛培南、亚胺培南几乎无耐药发生,肠炎沙门菌及鼠伤寒沙门菌对三代头孢菌素产生不同程度耐药(分别为7.69%和16.67%)。部分感染患儿经头孢噻肟(13例),头孢曲松(11例)治疗效果良好。9例难治性患儿升级抗生素或联合用药治疗后疗效尚满意。结论:粪便培养是确诊非伤寒沙门菌性肠炎的重要方法,结合药敏试验选择敏感抗生素治疗,可取得良好效果。     

医院感染革兰阴性杆菌的耐药性监测

目的：监测我院病房分离的100株革兰阴性杆菌对12种抗生素的耐药率,以指导临床用药。方法：采用Etest药敏试验测定我院分离的100株革兰阴性杆菌对12种抗生素的最低抑菌浓度（MIC）。结果：这12种抗生素中总耐药率最低的是亚胺培南（7％）,头孢吡肟（13％）,舒普深（14％）．阿米卡星（14％）;49株大肠埃希菌及肺炎克雷伯菌中,超广普β-内酰胺酶的发生率为43％;大肠杆菌对环丙沙星的耐药率高达76．5％;大肠埃希菌,肠杆菌属,不动杆菌,克雷伯菌属对亚胺培南的耐药率小于等于5．0％。结论：亚胺培南,头孢吡肟,舒普深,阿米卡星对革兰阴性杆菌的耐药率最低。     

北京大型社区成人感染性腹泻肠道致病菌监测与耐药性分析

目的了解北京大型社区成人感染性腹泻的致病菌与耐药性,为肠道传染病防控和临床合理使用抗菌药提供依据。方法回顾性分析北京某大型社区2015年至2018年连续4年的4月至10月期间1847例成人肠道门诊腹泻的肠道致病菌和药敏数据。Vitek2 Compact全自动微生物鉴定药敏分析系统进行细菌鉴定,凝集试验进行血清分型,K.B纸片扩散法测定抗菌药物敏感性。结果2015年至2018年肠道致病菌检出率约12.3%,前4位的致病菌分别为副溶血弧菌(51.5%)、沙门菌属(16.3%)、气单胞菌属(11.4%)和类志贺邻单胞菌(7.0%)。肠道致病菌主要检出于7月和8月两个月,沙门菌属易高发于5月。副溶血弧菌、气单胞菌属对氨苄西林耐药率高外,对其他抗菌药均较敏感。但沙门菌属的耐药性偏高,环丙沙星敏感率为62.2%,头孢曲松耐药率10.8%。结论本地区感染性腹泻患者的致病菌主要为副溶血弧菌,而沙门菌属耐药性高,应加强感染性腹泻肠道病原菌及耐药性的监测,指导传染病防控和临床治疗。     

多重耐药鲍曼不动杆菌的耐药性与AmpC耐药基因的研究

目的了解我院临床分离的60株多重耐药鲍曼不动杆菌（multi-drug resistant Acinetobater baumannii,MDRAB）的耐药性和AmpC耐药基因的存在状况。方法采用VITEK-2全自动细菌鉴定仪检测鲍曼不动杆菌对18种抗生素的药敏结果,对该细菌进行总DNA的提取,用聚合酶链反应（PCR）检测耐药基因,结合药物敏感试验分析菌株的耐药特征。结果检出结构基因ampC型49株,占81.7%;blaADC基因型50株,占83%;ACT基因型2株;41株菌同时携带blaADC和ampC结构基因,占68%;2株同时携带blaADC、ACT和ampC结构基因;未检测到其它AmpC耐药基因（MOX、CIT、FOX、DHA）。携带AmpC耐药基因的菌株耐药率高,特别是对头孢曲松、氨苄西林、头孢替坦、头孢唑啉、呋喃妥因的耐药率已接近或达到100%,而对于丁胺卡那霉素和头孢哌酮/舒巴坦的耐药率最低,分别为5%和20%。结论多重耐药鲍曼不动杆菌的blaADC耐药基因和ampC结构基因同时携带率高,并且是鲍曼不动杆菌多重耐药的主要原因。     

广州市市售食品沙门菌污染状况及耐药性分析

目的按国家食源性致病菌监测项目要求,对广州市市售食品的沙门菌污染状况以及对抗生素的药物敏感性进行调查。方法采集广州肉菜市场、大型超市、饭店提供的肉、水产品、凉拌菜及沙拉冷饮食品,按国标方法进行沙门菌检测,并用纸片法进行抗生素敏感性测定。结果 413份食品中有41份检出沙门菌,检出率为9.9%,其中生肉类食品的污染状况最为严重,检出率达18.8%,其次是生吃水产品为14.0%,熟肉和凉拌菜较低分别为4.5%和3.9%。在检出的17种血清型中德尔卑沙门菌比例最高为29.3%。对16株抗生素的药敏试验结果显示,对四环素耐药率最高,达61.0%;并且发现有6株多重耐药菌株以及对头孢类耐药的菌株。结论广州市市售食品中存在沙门菌污染,并存在有多重耐药和对头孢类抗生素耐药的现象。     

儿童沙门菌肠炎临床用药疗效比较分析

目的总结近两年内我科沙门菌临床特征,回顾性分析比较141 例沙门菌肠炎用药疗效,以提高临床治愈率遥方法141 例沙门菌肠炎根据大便培养药敏结果分为对茁-内酰胺类抗生素敏感组和耐药组,比较两组间平均住院日统计学差异,并根据 选择不同抗菌药进行疗效对比遥结果本文中沙门菌属对茁-内酰胺类抗生素耐药率高达23.40%曰耐药菌组较敏感菌组平均住 院日稍长（约0.05）曰敏感菌组内头孢呋辛疗效差,与头孢曲松尧头孢哌酮他唑巴坦钠和头孢他啶疗效相比,差异有统计学意 义（约0.05）,头孢三代抗菌药疗效相比较差异无统计学意义曰耐药菌组中口服复方新诺明片和庆大霉素片总有效率高,头孢哌 酮钠他唑巴坦钠在头孢组中总有效率最高遥结论细菌性肠炎应尽早行大便培养明确致病菌,并获得药物敏感信息指导临床用 药曰沙门菌属茁-内酰胺类抗生素敏感菌,首选三代头孢,茁-内酰胺类抗生素耐药菌可选用带酶抑制剂的三代头孢,或根据药物 敏感结果选用口服复方新诺明片和庆大霉素片遥     

多重耐药鲍曼不动杆菌的耐药分子机制及质粒谱分析

目的了解我院临床分离的66株多重耐药鲍曼不动杆菌（MDRAB）的耐药性和整合子（qacE△1-sull）、转座子（tnpU）存在状况,并对菌株质粒谱进行分析。方法采用VITEK-2全自动细菌鉴定仪检测鲍曼不动杆菌对18种抗生素的药敏结果,并对该细菌进行总DNA的提取。用聚合酶链反应（PCR）检测qacE△1-sull及tnpU,提取质粒进行同源性分析。结果 66株鲍曼不动杆菌中整合子qacE△1-sull基因阳性率为31.8%,转座子tnpU基因阳性率为30.3%。携带遗传标记的菌株耐药率高,特别是对头孢曲松、氨苄西林、头孢替坦、头孢唑啉、呋喃妥因的耐药率已接近或达到100%,而对丁胺卡那霉素和头孢哌酮/舒巴坦的耐药率最低,分别为5%和20%;有19株对亚胺培南耐药,其中整合子阳性率63.2%,转座子阳性率36.8%。检出质粒的46株（70%）临床分离菌出现1～3条大质粒带,大小在1～20kb间,其中出现1条带的有33株、2条带8株、3条带5株,有12株菌提取到大小相同的质粒。结论多重耐药鲍曼不动杆菌耐亚胺培南的耐药现象严重;整合子、转座子遗传标记的携带率高,可能是鲍曼不动杆菌多重耐药的主要原因。     

2007-2009年重庆市沙门菌监测

目的 掌握重庆市沙门菌菌型种类及药物耐药特征,为制定预防控制措施提供科学依据。方法 确定监测病例的定义及监测点,对在医疗机构就诊的腹泻病例和腹泻病暴发疫情中的腹泻病例进行沙门菌监测。结果 2007-2009年共监测沙门菌病例162例,19种血清型,夏秋季为发病高峰,血清型以鼠伤寒和肠炎沙门菌为主。25起腹泻病暴发疫情均为沙门菌感染,其中11起疫情患者发病前食用了凉拌皮蛋,临床表现以腹泻,伴发热、腹痛为主。结论 鼠伤寒沙门菌致泻性较为严重,而肠炎沙门菌感染发热、腹痛症状明显。19种血清型沙门菌对头孢噻肟均敏感,对萘啶酮酸耐药率最高。加强食品的监督管理和改变食用方式是降低发病的重要干预措施。     

腹泻相关致病菌基因芯片的制备及应用

目的确定引起人类感染性腹泻的11种病原微生物,并制备芯片用于检测门诊腹泻患者粪便标本中的致病菌。方法根据本院2009年1月至2012年12月期间腹泻门诊的粪便病原菌检测数据,采用生物信息学的方法,收集11种病原菌的所有基因序列,设计引物及探针,优化并制备芯片,PCR扩增杂交并对杂交结果进行分析。用该芯片对本院保存的163个肠道致病菌临床分离株进行鉴定来评价芯片的特异性,用芯片来检测掺有不同浓度沙门氏菌的粪便标本评价芯片的灵敏度。同时收集2010年6月至2013年3月在本院就诊的1052份腹泻患者粪便标本,平行进行PCR扩增、细菌培养、基因芯片检测,比较不同检测方法的阳性率。结果成功制备了腹泻相关11种致病菌检测芯片。应用制备的芯片检测了163个临床分离株,准确率达100％。与PCR方法比较,基因芯片检测沙门氏菌的灵敏度达102CFU／ml,比PCR法检测灵敏度高10倍。用该芯片对临床1052份腹泻患者腹泻标本进行检测,与传统的培养法及PCR法比较,有较高的阳性检出率,达36％,比常规细菌培养阳性率高13％（X2=2．28,P〈0．05）,比PCR检出率高4％（X2=5．16,P〉0．05）。结论成功制备11种腹泻相关致病菌基因芯片,能同时对11种腹泻致病菌进行检测,有较好的特异性和灵敏度,有更高的阳性率,可以用于临床检测。     

2007—2008年北京大学深圳医院急性感染性腹泻细菌病原学监测结果分析

目的了解2007年7月至2008年7月间北京大学深圳医院急性感染性腹泻的流行病学特征。以便及时采取措施以防传染病暴发流行。方法选择每日排便≥3次的患者作为研究对象,在患者未使用抗菌药物之前进行大便细菌病原学检验并进行统计分析。结果共检测1017份标本,检出病原菌133株,阳性率为13．07％。133株病原菌中,致病性大肠埃希菌、副溶血弧菌、产毒大肠埃希菌、侵袭性大肠埃希菌、沙门菌分别分离出43株（32．34％）、37株（27．82％）、19株（14．28％）、18株（13．54％）和13株（9．77％）。夏秋季检出肠道致病菌90株（67．66％）,高于春冬季节的43株（32．34％）。结论不仅要针对各病原菌检出率的差异在不同季节开展相应的防控措施,还要结合地域的特点对特定的病原菌进行重点监测。     

The isolation of antibiotic-resistant salmonella from retail ground meats

BACKGROUND: Salmonella is a leading cause of foodborne illness. The emergence of antimicrobial-resistant salmonella is associated with the use of antibiotics in animals raised for food; resistant bacteria can be transmitted to humans through foods, particularly those of animal origin. We identified and characterized strains of salmonella isolated from ground meats purchased in the Washington, D.C., area. METHODS: Salmonella was isolated from samples of ground chicken, beef, turkey, and pork purchased at three supermarkets. The isolates were characterized by serotyping, antimicrobial-susceptibility testing, phage typing, and pulsed-field gel electrophoresis. The polymerase chain reaction and DNA sequencing were used to identify resistance integrons and extended spectrum beta-lactamase genes. RESULTS: Of 200 meat samples, 41 (20 percent) contained salmonella, with a total of 13 serotypes. Eighty-four percent of the isolates were resistant to at least one antibiotic, and 53 percent were resistant to at least three antibiotics. Sixteen percent of the isolates were resistant to ceftriaxone, the drug of choice for treating salmonellosis in children. Bacteriophage typing identified four isolates of Salmonella enterica serotype typhimurium definitive type 104 (DT104), one of DT104b, and two of DT208. Five isolates of S. enterica serotype agona had resistance to 9 antibiotics, and the two isolates of serotype typhimurium DT208 were resistant to 12 antibiotics. Electrophoretic patterns of DNA that were indistinguishable from one another were repeatedly found in isolates from different meat samples and different stores. Eighteen isolates, representing four serotypes, had integrons with genes conferring resistance to aminoglycosides, sulfonamides, trimethoprim, and beta-lactams. CONCLUSIONS: Resistant strains of salmonella are common in retail ground meats. These findings provide support for the adoption of guidelines for the prudent use of antibiotics in food animals and for a reduction in the number of pathogens present on farms and in slaughterhouses. National surveillance for antimicrobial-resistant salmonella should be extended to include retail meats.     

Ceftriaxone-resistant salmonella infection acquired by a child from cattle

BACKGROUND: The emergence of resistance to antimicrobial agents within the salmonellae is a worldwide problem that has been associated with the use of antibiotics in livestock. Resistance to ceftriaxone and the fluoroquinolones, which are used to treat invasive salmonella infections, is rare in the United States. We analyzed the molecular characteristics of a ceftriaxone-resistant strain of Salmonella enterica serotype typhimurium isolated from a 12-year-old boy with fever, abdominal pain, and diarrhea. METHODS: We used pulsed-field gel electrophoresis and analysis of plasmids and beta-lactamases to compare the ceftriaxone-resistant S. enterica serotype typhimurium from the child with four isolates of this strain obtained from cattle during a local outbreak of salmonellosis. RESULTS: The ceftriaxone-resistant isolate from the child was indistinguishable from one of the isolates from cattle, which was also resistant to ceftriaxone. Both ceftriaxone-resistant isolates were resistant to 13 antimicrobial agents; all but one of the resistance determinants were on a conjugative plasmid of 160 kb that encoded the functional group 1 beta-lactamase CMY-2. Both ceftriaxone-resistant isolates were closely related to the three other salmonella isolates obtained from cattle, all of which were susceptible to ceftriaxone. CONCLUSIONS: This study provides additional evidence that antibiotic-resistant strains of salmonella in the United States evolve primarily in livestock. Resistance to ceftriaxone, the drug of choice for invasive salmonella disease, is a public health concern, especially with respect to children, since fluoroquinolones, which can also be used to treat this disease, are not approved for use in children.     

2010年广州某医疗中心儿童夏季细菌性腹泻的病原学调查

目的研究广州地区小儿夏季细菌性腹泻的病原菌分布。方法采集2010年5～7月广州市妇女儿童医疗中心珠江新城院区腹泻患儿的大便标本进行常规病原菌的分离培养,通过生化反应和血清凝集试验进行鉴定和分型,并使用金标法对空肠弯曲菌抗原进行检测。结果从110份标本中检出44株病原菌,检出率为40.0%。其中致病性大肠埃希菌17株,2岁以下患儿检出15株;空肠弯曲菌12株,2岁以下患儿检出10株;沙门菌6株;念珠菌纯生长6株;产气荚膜杆菌3株。结论广州地区夏季儿童细菌性腹泻的主要病原菌是致病性大肠埃希菌及空肠弯曲菌,两者的易感人群以2岁以下婴幼儿为主。     

Characteristics of non-typhoidal Salmonella isolates from human and broiler-chickens in southwestern Seoul, Korea

Non-typhoidal Salmonella (NTS) is an important commensal microorganism. The purpose of this study was to determine the epidemiological relation between NTS isolates from livestock and NTS isolates from human by analyzing antimicrobial susceptibilities and performing molecular typing. We determined the serotypes of 36 human clinical isolates and 64 livestock isolates, performed antimicrobial susceptibility testing against 8 antibiotics, and determined the molecular types of isolated NTS spp. by pulsed field gel electrophoresis (PFGE). In human isolates, S. enteritidis was the most common serotype (17 isolates; 47.2%) and S. typhimurium the second most (8 isolates; 22.2%). In livestock isolates, S. typhimurium was the most common serotype (15 isolates; 23.44%), and S. enteritidis was the second most (14 isolates; 21.88%). Ampicillin and tetracycline resistance were 50% (32/64 isolates) each among broiler-chicken NTS isolates. No human or livestock NTS isolates showed resistance to ciprofloxacin, TMP-SMX, or ceftriaxone. However, 19.4% (7/36) and 46.8% (30/64) of the human and livestock NTS isolates were resistant to nalidixic acid (MIC > or = 16 mg/mL), respectively. The presence of the three identical PFGE molecular types from human and broiler-chicken NTS isolates suggests the possibility of transmission from livestock to humans.     

ABC chromogenic agar: a cost-effective alternative to standard enteric media for Salmonella spp. isolation from routine stool samples

Salmonellosis is the second most common cause of bacterial gastroenteritis, yet the yield from routine stool culture is low. Commonly used selective enteric media have poor specificities for salmonella identification, resulting in a high laboratory workload. A special chromogenic medium, ABC agar, is a promising alternative but its cost-effectiveness has not been evaluated in diagnostic laboratories. A collaborative study is therefore undertaken in two district general hospitals laboratories. Routine stool samples (n=866) were subcultured onto ABC agar half plates after selective enrichment in selenite broth. Similarly, 246 and 620 stool samples were subcultured onto desoxycholate lactose sucrose (DCLS) and xylose lactose desoxycholate (XLD) whole agar plates, respectively. Salmonella spp. were isolated from only 14 (1.6%) of stool samples tested. Specificity was significantly higher for ABC (98%) than DCLS (67%) or XLD (78%) agars. Welcan workload units (ABC 4.8, XLD and DCLS both 7.3) and costs per specimen (ABC 1.26 pounds sterling, DCLS 3.81 pounds sterling and XLD 1.83 pounds sterling) were similarly lower with ABC agar. The results indicate that ABC chromogenic agar offers improvements in specificity, workload and costs over conventional enteric media for Salmonella spp. isolation.     

惠州市区腹泻病人沙门菌感染水平研究

目的了解和掌握惠州市区腹泻患者沙门菌感染情况及菌型分布。方法采集定点医院就诊的腹泻患者粪便标本,采用传统方法与荧光定量PCR方法相结合检测沙门菌,用SPSS17.0软件对数据进行统计分析。结果 2472例腹泻患者中,检出沙门菌44例,阳性率为1.78%,共分离出7种血清型,其中鼠伤寒沙门菌26株,斯坦利沙门菌7株,肠炎沙门菌5株,雷根特沙门菌、德尔卑沙门菌各2株,乙型副伤寒沙门菌、阿贡纳沙门菌各1株。结论惠州市区腹泻患者主要以鼠伤寒沙门菌、斯坦利沙门菌和肠炎沙门菌感染引起的腹泻为主。通过加强对腹泻门诊腹泻患者沙门菌的监测,为防止食源性疾病的发生和控制起到良好的预警作用。     

An outbreak of multidrug-resistant, quinolone-resistant Salmonella enterica serotype typhimurium DT104.

BACKGROUND: Food-borne salmonella infections have become a major problem in industrialized countries. The strain of Salmonella enterica serotype typhimurium known as definitive phage type 104 (DT104) is usually resistant to five drugs: ampicillin, chloramphenicol, streptomycin, sulfonamides, and tetracycline. An increasing proportion of DT104 isolates also have reduced susceptibility to fluoroquinolones. METHODS: The Danish salmonella surveillance program determines the phage types of all typhimurium strains from the food chain, and in the case of suspected outbreaks, five-drug-resistant strains are characterized by molecular methods. All patients infected with five-drug-resistant typhimurium are interviewed to obtain clinical and epidemiologic data. In 1998, an outbreak of salmonella occurred, in which the strain of typhimurium DT104 was new to Denmark. We investigated this outbreak and report here our findings. RESULTS: Until 1997, DT104 infections made up less than 1 percent of all human salmonella infections. The strain isolated from patients in the first community outbreak of DT104 in Denmark, in 1998 was resistant to nalidixic acid and had reduced susceptibility to fluoroquinolones. The outbreak included 25 culture-confirmed cases. Eleven patients were hospitalized, and two died. The molecular epidemiology and data from patients indicated that the primary source was a Danish swine herd. Furthermore, the investigation suggested reduced clinical effectiveness of treatment with fluoroquinolones. CONCLUSIONS: Our investigation of an outbreak of DT104 documented the spread of quinolone-resistant bacteria from food animals to humans; this spread was associated with infections that were difficult to treat. Because of the increase in quinolone resistance in salmonella, the use of fluoroquinolones in food animals should be restricted.