氨苄西林耐药流感嗜血杆菌β-内酰胺酶基因分析

目的了解深圳市宝安区氨苄西林耐药流感嗜血杆菌β-内酰胺酶基因分布特征,为临床合理用药提供依据。方法用K-B法检测氨苄西林耐药性,头孢硝噻酚纸片法检测β-内酰胺酶,TEM型和ROB-1型基因采用PCR扩增和序列分析法。结果检出62株氨苄西林耐药流感嗜血杆菌,其中60株β-内酰胺酶阳性。60株β-内酰胺酶阳性株中58株检出TEM-1型基因,占96.7%,1株检出ROB-1型基因,占1.7%,1株未检出基因型。结论产TEM-1型β-内酰胺酶是流感嗜血杆菌主要耐药机制,但β-内酰胺酶阴性氨苄西林耐药株的出现更值得关注。     

肺炎链球菌β-内酰胺酶TEM基因的发现

目的：探讨肺炎链球菌是否产β-内酰胺酶。方法：对2002年9月至2003年4月在苏州大学附属儿童医院就诊的呼吸道感染患儿痰标本中分离到的23株肺炎链球菌进行β-内酰胺酶TEM基因PCR检测与PCR扩增产物直接测序分析。结果：23株肺炎链球菌经TEM基因PCR检测21株阳性，阳性率达91．3％。测得1号菌株(SR001)基因序列为TEM-1型，已登录美国国立生物信息中心，注册号：AY392531。结论：从肺炎链球菌中检出β-内酰胺酶TEM基因。肺炎链球菌对青霉素耐药机制包括产β-内酰胺酶。     

产超广谱β-内酰胺酶大肠埃希菌耐药表型和基因型分析

目的:分析临床分离大肠埃希菌耐药性、产超广谱β-内酰胺酶(ESBLs)阳性率及耐药基因之间的关系。方法:用K-B法检测117株大肠埃希菌耐药性,用酶抑制剂增强实验纸片法检测产ESBLs菌株,用PCR法检测相关耐药基因,用DNA序列分析确认基因亚型。结果:117株大肠埃希菌产ESBLs 49株,阳性率41.9%。产ESBLs菌株对青霉素类和第一、第二代头孢菌素耐药率100%,对第三代头孢菌素中头孢哌酮、头孢噻肟和头孢曲松耐药率>95%,对酶抑制剂哌拉西林/三唑巴坦和头孢哌酮/舒巴坦耐药率<20%,未检测到亚胺培南耐药株。非产ESBLs菌株耐药率明显低于产ESBLs菌株。49株产ESBLs菌株PCR均扩增到CTX-M型耐药基因,44株扩增到TEM型基因,未扩增到其他基因型。DNA序列分析证实为CTX-M-14亚型、CTX-M-3亚型和广谱酶TEM-1亚型基因。结论:大肠埃希菌产ESBLs较高,耐药显著;耐药基因以CTX-M-14亚型为主,其次为CTX-M-3亚型,尚未检出其他ESBLs基因。TEM-1亚型广谱内酰胺酶基因在大肠埃希菌中普遍存在。     

临床分离大肠杆菌产β-内酰胺酶与耐氨苄青霉素关系的初步探讨

采用Nitrocefin法和琼脂稀释法对本室近6年从临床分离的322株大肠杆菌的β-内酰胺酶及对氨苄青霉素耐药进行了检测，并就两者的关系进行了初步探讨．结果显示：322株大肠杆菌，78．9％的菌株产β-内酰胺酶，70．2％的菌株对氨苄青霉素耐药；产β-内酰胺酶菌株有84．2％耐氨苄青霉素，而非产β-内酰胺酶菌株仅有17．7％耐氨苄青霉青，经x2检验，P＜0．01．表明临床分离大肠杆菌在产β-内酰胺酶和耐氨苄青霉素方面均较为普通，且产β-内酰胺酶是其对氨苄青霉素耐药的主要途径．     

革兰阴性杆菌TEM型β-内酰胺酶耐药基因研究

目的 了解中南大学3所附属医院产超广谱β-内酰胺酶(ESBLs)革兰阴性杆菌TEM型耐药基因的检出及流行情况.方法 收集254株多重耐药革兰阴性杆菌,采用双纸片协同法(DDS)进行ESBLs表型确证,多重PCR.法扩增blaTEM、blaSHV、blaOXA-1基因,TEM特异性引物对其整个开放阅读框进行扩增并对PCIL产物测序,通过BLAST分析确定基因型;并对携带有TEM基因的革兰阴性菌株用随机扩增多态DNA(RAPD)方法进行菌株的同源性分析.结果 经多重PCR扩增,105株肠杆菌获得阳性结果,其中85株菌携带TEM基因,26株菌携带SHV基因,10株菌携带OXA-1基因;6株非发酵菌获得阳性结果,均携带TEM基因,且全部为TEM-1型广谱β-内酰胺酶.携带blaTEM耐药基因的菌株所含RAPD类型:大肠埃希菌12种,肺炎克雷伯菌6种,阴沟肠杆菌7种.结论 TEM-1型β-内酰胺酶是湖南地区主要流行的TEM型酶;大肠埃希菌产TEM酶情况尤为突出;在同一医院以及同一病区存在TEM-1型β-内酰胺酶的克隆传播.     

耐氨苄西林流感嗜血杆菌产β-内酰胺酶机制研究

目的：探讨耐氨苄西林的流感嗜血杆菌产生β－内酰胺酶的机制。方法：对临床分离的１１２株流感嗜血杆菌耐药菌用纸片法作β－内酰胺酶测定，用ＰＣＲ法检测产酶流感嗜血杆菌中的β－内酰胺酶基因的存在。结果：纸片法测得产酶菌株３２株，产酶率２８．６％ （３２／１１２）；３２株产酶菌中ＰＣＲ法测β－内酰胺酶基因阳性菌株２９株，阳性率为９０．６％ （２９／３２），其中质粒ＤＮＡ 模板组阳性为２５株，基因组ＤＮＡ模板组阳性为４例。结论：（１）流感嗜血杆菌耐氨苄西林主要由质粒介导产生β－内酰胺酶所造成。（２）ＰＣＲ法是研究流感嗜血杆菌是否携带β－内酰胺酶基因及该基因所在位置的简便而有效的方法。     

临床分离大肠杆菌产β^—内酰胺酶与耐氨苄青霉素关系的初步…

采用Ｎｉｔｒｏｃｅｆｉｎ法和琼脂稀释法对本室近６年从临床分离的３２２株大肠杆菌的β内酰胺酶及对氨苄青霉素耐药进行了检测，并就两的关系进行了初步探讨，结果显示：３２２株大肠杆菌，７８．９％的菌株产生β内酰胺酶，７０．２％的菌株对氨苄青霉素耐药，产β内酰胺酶菌株有８４．２％耐氨苄青霉素，而非产β－内酰胺酶菌株仅有１７．７％耐氨苄青霉素，经Ｘ＾２检验，Ｐ〈０．０１，表明临床分离大肠杆菌在产β内酰胺酶和     

海南地区2011年四环素高度耐药淋球菌terM基因分型

目的了解海南地区四环素高度耐药淋球菌（TRNG）的分子流行病学情况。方法采用琼脂稀释法检测TRNG菌株,PCR方法对TRNG菌株鉴定并进行term基因分型;纸片酸度法测定产β-内酰胺酶菌株（PPNG）,PCR方法鉴定B-内酰胺酶质粒并行TEM-1基因分型。结果2011年检测101株淋球菌,检出TRNG54株（53．47％）,其中22株（40．74％）对四环素和青霉素耐药;tetM基因分型结果显示52株为荷兰型,有2株为美国型。22株对四环素和青霉素耐药株的TEM-1基因分型21株为亚洲型,1株非洲型且合并美国型;未见多伦多型、里约型。结论海南地区TRNG流行株以荷兰型tetM基因为主（96．30％）,美国型偶见。     

鲍曼不动杆菌TEM-1型ESBLs基因及其多重耐药的研究

目的分析产TEM-1型超广谱β-内酰胺酶（ESBLs）鲍曼不动杆菌的耐药性及其基因序列。方法用聚合酶链式反应（PCR）扩增产ESBLs鲍曼不动杆菌的TEM-1型耐药基因，用克隆测序方法分析质粒上TEM-1型ESBLs基因。结果15株产ESBLs鲍曼不动杆菌中，TEM-1型ESBLs阳性菌株有12株，TA克隆后测序表明，与鲍曼不动杆菌（AY560328．1）bla TEM-1基因序列99％源。结论质粒上带产TEM-1型ESBLs的鲍曼不动杆菌，bla TEM-1基因与鲍曼不动杆菌多重耐药密切相关。     

多重耐药鲍曼不动杆菌β-内酰胺酶基因型研究

目的:了解我院临床分离的多重耐药鲍曼不动杆菌β-内酰胺酶基因分布情况。方法:用三维试验检测15株多重耐药鲍曼不动杆菌ESBLs、AmpC、MBL(金属β-内酰胺酶)产酶情况;用PCR方法检测各种β-内酰胺酶基因。结果:三维试验检出2株菌产ESBLs;9株菌产AmpC;3株菌合产ESBLs和AmpC酶;3株菌产MBL(均同时产AmpC)。PCR检出15株菌均携带blaTEM基因;2株菌携带blaPER-1基因;14株菌携带AmpC基因;未检出产金属β-内酰胺酶基因。结论:我院多重耐药的鲍曼不动杆菌多含有blaTEM基因和AmpC基因,也首次发现部分产PER型ES-BLs鲍曼不动杆菌。     

Resistance of clinical isolates of Haemophilus influenzae in United Kingdom 1986

Between 1 January and 31 March 1986, 2434 strains of Haemophilus influenzae collected from 23 laboratories in the United Kingdom were examined. With the same criteria as previous studies in 1977 and 1981 the prevalence of resistance was: ampicillin 7.8% (6.2% beta-lactamase producers and 1.6% non-producers), tetracycline 2.7%, chloramphenicol 1.7%, trimethoprim 4.2%, and sulphamethoxazole 3.5%. of the 87 capsulated strains, 15 produced beta-lactamase, nine were resistant to ampicillin but did not produce beta-lactamase, and two strains, one of which produced beta-lactamase, were resistant to chloramphenicol and tetracycline. Since 1977 the prevalence of resistance to ampicillin, chloramphenicol, and trimethoprim has increased significantly. During 1981-6 strains resistant to ampicillin but not producing beta-lactamase and strains resistant to trimethoprim have significantly increased.     

2012至2015年昆明医科大学第一附属医院流感嗜血杆菌耐药性监测

目的 了解昆明医科大学第一附属医院临床分离的流感嗜血杆菌对常用抗菌药物的耐药情况, 为临床合理使用抗生素提供依据.方法 收集2012年1月至2015年12月184株临床分离的流感嗜血杆菌, 采用纸片扩散法 (K-B法) 进行抗菌药物敏感性试验, Nitrocefin纸片检测定β-内酰胺酶, 用WHONET5.6软件对流感嗜血杆菌耐药率进行统计分析.结果 184株临床分离的流感嗜血杆菌对氨苄西林耐药率最高, 达46.7%, 其次对氯霉素、氨苄西林/舒巴坦耐药率分别为23.2%、13%.该菌对阿奇霉素、环丙沙星、美洛培南、头孢呋辛、头孢噻肟的耐药率均在10%以下.儿童分离株对氨苄西林的耐药率 (56.9%) 高于成人分离株 (42.1%) ;除环丙沙星、美洛培南和氯霉素外, 儿童株对其他测试抗菌药物的耐药率均较成人株高.产β-内酰胺酶株总检出率为52.8%, 其中儿童分离株产酶检出率为64.3%高于成人分离株产酶检出率47.6%.共检出氨苄西林耐药而β-内酰胺酶阴性菌株1株, 占0.5%.结论 流感嗜血杆菌主要分离自住院患者呼吸道分泌物标本.虽然该菌对头孢菌素类、大环内酯类、酶抑制剂复方制剂、喹诺酮类、碳青霉烯酶类抗菌药物保持良好的抗菌活性, 但是产β内酰胺酶仍是流感嗜血杆菌的重要耐药机制, 表现为氨苄西林耐药率较高, 因此不建议作为流感嗜血杆菌感染的经验性治疗.     

Susceptibility of Haemophilus influenzae to antimicrobial agents used in Canada. Canadian Study Group.

We evaluated the incidence of Haemophilus influenzae resistance to selected antimicrobials used in Canada. From 1985 to 1987, 2503 H. influenzae isolates obtained in 14 hospitals across Canada were sent to the Centre hospitalier de l'université Laval (CHUL) for identification, serotyping, biotyping and testing for beta-lactamase production. Susceptibility tests were done with the use of 12 antibiotics. Of the strains 424 (16.9%) produced beta-lactamase; the proportion varied from 12.8%, in Newfoundland, to 19.6%, in Ontario. Of the strains 18.3% were type b; 19.4% of those produced beta-lactamase. Almost 82% of the strains were not type b. The proportion of beta-lactamase-producing strains varied according to the isolation site, from 15.3% in the respiratory tract to 25.6% in the blood. The overall level of resistance was 19.3% to ampicillin, 24.2% to erythromycin, 3.8% to trimethoprim-sulfamethoxazole, 1.7% to amoxicillin-potassium clavulanate, 1.4% to cefaclor, 1.3% to tetracycline, 1.0% to rifampin, 0.7% to cefuroxime and 0.1% to cefamandole. Disc diffusion susceptibility testing revealed 64 strains (2.6%) that did not produce beta-lactamase but were resistant to ampicillin and 9 (0.4%) that produced beta-lactamase but were susceptible to ampicillin. The results of beta-lactamase production tests were identical regardless of whether the tests were done by the CHUL or by the other hospitals, but there was a marked difference in the susceptibility test results between the CHUL and the other centres. Our results suggest that the level of resistance of H. influenzae to antibiotics is increasing in Canada and that the initial choice of drug therapy may have to be modified.     

某院肺炎克雷伯菌产质粒AmpC酶基因型及耐药性研究

目的调查该院临床分离肺炎克雷伯菌产质粒AmpC酶表型和基因型携带情况及其对常用抗生素的耐药性,为临床合理用药提供参考。方法采用Vitek2-compact全自动细菌鉴定药敏系统对临床分离菌株进行鉴定及药物敏感试验,采用头孢西丁三维试验检测AmpC酶表型,采用多重PCR方法检测AmpC基因并经DNA测序确定其基因型别。结果 2010年7月至2011年6月共分离到116株肺炎克雷伯菌,产AmpC酶肺炎克雷伯菌占18.1%(21/116)。产AmpC酶肺炎克雷伯菌多重耐药情况严重,对氨基糖甙类、喹诺酮类及大多数头孢菌素类抗菌药物的耐药率在57.1%～100%,对加酶抑制剂复合药氨苄西林/舒巴坦、阿莫西林/克拉维酸、头孢哌酮/舒巴坦及哌拉西林/他唑巴坦的耐药率分别为90.5%、85.7%、42.9%、38.1%,所有菌株对碳青霉烯类抗生素亚安培南和美罗培南仍全部敏感。产AmpC酶菌株对头孢西丁、第3代头孢菌素及氨苄西林/舒巴坦、阿莫西林/克拉维酸等抗生素的耐药率明显高于不产酶株(P<0.05)。21株产酶菌株均携带DHA-1型AmpC酶基因。结论该院肺炎克雷伯菌产AmpC酶株检出率较高,产酶菌株多重耐药情况严重。临床应根据药敏结果合理选用抗菌药物,以减少耐药菌株的产生。     

179株β-内酰胺酶阳性细菌的体外药敏试验

目的：探讨β－ 内酰胺酶阳性菌的抗药性。方法：从２１７ 株临床革兰阴性杆菌和革兰阳性葡萄球菌中测得β－ 内酰胺酶阳性者１７９ 株。采用 Ｋ－ Ｂ 法测定舒普深、优力新和安美汀对这１７９ 株细菌的体外药敏试验,并与头孢哌酮、氨苄青霉素、羟氨苄青霉素及其他一些抗生素进行比较。结果说明：３ 种复方制剂对产酶细菌的抗菌作用较相应单药均有不同程度的增效。此外,对产酶革兰阴性杆菌舒普深效果较好,对产酶葡萄球菌优力新效果较好。     

2000～2002年北京、上海及广州三地儿童携带流感嗜血杆菌抗生素敏感性监测

目的了解当前我国儿童携带流感嗜血杆菌对常用抗生素的敏感性情况,以便有效指导临床合理用药和预防.方法采用E-test最小抑菌浓度 (MIC) 方法及KB纸片扩散法对2000～2002年北京、上海、广州3所儿童医院上呼吸道感染儿童携带流感嗜血杆菌进行10种常用抗生素敏感性检测.结果氨苄青霉素对898株流感嗜血杆菌的MIC50和MIC90分别为0.25 μg/ml和4 μg/ml,敏感性88.0%,10.6%菌株对氨苄青霉素耐药,所有氨苄青霉素中度敏感株和耐药株均产β-内酰胺酶,分离株产β-内酰胺酶率为12%;分离株对阿莫西林/克拉维酸、头孢曲松、头孢呋辛敏感性均为100%;头孢克罗对分离株MIC50和MIC90分别为1.5 μg/ml和3 μg/ml,敏感性略低(96.1%),耐药率1.8%.流感嗜血杆菌对阿奇霉素、环丙沙星敏感率分别为100%和99%,对氯霉素、四环素、磺胺甲(口恶)唑/甲氧苄氨嘧啶(SMZ/TMP)耐药率分别为11%、18%、54.4%.北京和上海分离株对四环素敏感性分别为57%和61%,明显低于广州分离株(81%);广州和上海分离株对SMZ/TMP敏感性分别为47%和54%,明显高于北京株(35%);2000～2002年的3年中,分离株对氨苄青霉素敏感性呈逐年下降趋势,对氨苄青霉素总体耐药率由2000年的7.7%增加至2002年的14.5%.本研究中,34.5%分离株对8种抗生素均敏感,多重耐药株占12.8%, 敏感株的分布有地区差异.58.5%的分离株分布在5个常见耐药表型中,其中单一SMZ/TMP耐药最多(29.8%);其次,SMZ/TMP和四环素交叉耐药(12.5%),单纯四环素耐药居第三位(9.4%).氨苄青霉素不敏感株对头孢克罗、四环素、SMZ/TMP和氯霉素耐药率分别为23.5%、63.3%、74.5%和63.3%,明显高于氨苄青霉素敏感株(1.6%、51.4%、11.1% 和4.9%);氨苄青霉素与头孢克罗对菌株MIC值呈正相关,与SMZ/TMP和氯霉素对菌株抑菌能力呈负相关.结论三地儿童携带流感嗜血杆菌的产酶率正在上升,导致菌株对氨苄青霉素耐药性增加,分离株对部分抗生素的耐药性有明显地域差异,菌株对氨苄青霉素耐药性与其对氯霉素、SMZ/TMP、头孢克罗耐药性有明显相关性.     

Detection of toxigenic Clostridium difficile by polymerase chain reaction

ＤｅｔｅｃｔｉｏｎｏｆｔｏｘｉｇｅｎｉｃＣｌｏｓｔｒｉｄｉｕｍｄｉｆｆｉｃｉｌｅｂｙｐｏｌｙｍｅｒａｓｅｃｈａｉｎｒｅａｃｔｉｏｎＣｈｅｎＣｕｎｌｏｎｇ（陈村龙）；ＺｈｏｕＤｉａｎｙｕａｎ（周殿元）；ＰａｎＬｉｎｇｊｉａ（潘令嘉）；ＷａｎｇＪｉｄｅ（...     

河南省2010年柯萨奇病毒A组16型VP1区基因特征分析

目的了解河南省2010年柯萨奇病毒A组16型(CA16)流行株VP1区基因特征。方法对河南省2010年手足口病(HFMD)粪便和咽拭子样品中分离到的10株CA16病毒,采用反转录-聚合酶链反应(RT-PCR)方法进行VP1编码区基因扩增,对扩增产物进行测序,利用生物信息学软件对序列分析,与已报道的CA16标准株序列构建基因亲缘关系树。结果 10株CA16毒株,其VP1区核苷酸和氨基酸同源性分别为90.9%~100.0%,99.3%~100.0%,与国际CA16标准株G10在VP1区核苷酸和氨基酸同源性分别为67.0%~69.0%,72.0%~74.0%。亲缘进化树显示全部CA16株可分为A和B两个基因型,B基因型又可分为B1和B2两个基因亚型。河南省分离的CA16毒株全部属于B1基因亚型,同时包含B1a和B1b两条进化分支在河南省共同流行。结论河南省手足口病感染CA16病毒的流行株属B1基因亚型,有B1a和B1b两个进化分支共同进化和循环。     

Molecular detection and antimicrobial resistance of diarrheagenic Escherichia coli strains isolated from diarrheal cases

OBJECTIVE: To identify and classify Iranian isolates of diarrheagenic Escherichia coli (E. coli) on the basis of presence of virulence genes and to determine antibiotic susceptibility of isolated strains. METHODS: The current cross-sectional study was conducted in 2005 at the Pasteur Institute, Tehran, Iran. One hundred and ninety-three diarrheagenic E. coli isolated from diarrheal patients in different regions of Iran were included in current study. Virulence factor genes for diarrheagenic E. coli were detected by polymerase chain reaction. RESULTS: Of the 193 diarrheagenic E. coli detected by PCR, 86 (44.5%) were Shiga toxin-producing E. coli STEC, 74 (38.4%) enteropathogenic E. coli EPEC, 19 (9.8%) enteroaggregative E. coli, and 14 (7.3%) enterotoxigenic E. coli isolates. Susceptibility to 12 clinically important antimicrobial agents was determined for 193 strains of diarrheagenic E. coli. A high incidence of resistance to tetracycline (63%), ampicillin (62%), streptomycin (56%), amoxicillin/clavulanic acid (44.5%), trimethoprim/sulfamethoxazole (39.5%), and cephalothin (37%) was observed. CONCLUSION: The STEC and EPEC strains with high resistance to tetracycline and ampicillin, but highly susceptible to quinolones are among the most important causative agent of diarrhea in Iran. This study suggests that antimicrobial resistance is widespread among E. coli strains colonizing Iranian patients. Guidelines for appropriate use of antibiotics in developing countries require updating.     

Haemophilus infection in chronic obstructive pulmonary disease patients

Seventy sputum specimens from chronic obstructive pulmonary disease (C.O.P.D.) with secondary infection patients and 50 sputum specimens from C.O.P.D. patients without infection were cultured on blood agar plate, eosine-methylene blue agar plate, chocolate agar plate and selective medium chocolate agar plate. Haemophilus species was isolated from 20 specimens from C.O.P.D. with secondary infection patients. The isolation rate was 28.5%. Eight strains could produced beta-lactamase and were resistant to ampicillin (40%). One strain was resistant to ampicillin though without beta-lactamase production.