阴沟肠杆菌产超广谱β-内酰胺酶与AmpC酶基因及其流行病学研究

目的分析医院2008-2010年临床分离阴沟肠杆菌产ESBLs和AmpC酶及其对抗菌药物的耐药性,并了解其耐药基因的传播机制。方法采用改良三维试验筛选AmpC酶,双纸片扩散法检测ESBLs,聚合酶链反应(PCR)检测ESBLs和AmpC酶的基因,采用微量肉汤稀释法分析细菌耐药性,质粒接合试验分析耐药基因的传播特点。结果同时产ESBLs和AmpC酶菌株对三、四代头孢菌素及含酶抑制剂药物的耐药率均>50.0%;45株改良三维试验阳性,14株ESBLs确证试验阳性,ESBLs和AmpC酶的基因阳性者分别为25、38株,分别以TEM-1型、MIR-3型为主,其次为CTX-M-3、DHA-1型,SHV-11型广谱β-内酰胺酶2株,未检测到CIT、MOX、FOX、ACC型AmpC酶的基因,5株接合试验成功。结论阴沟肠杆菌主要携带TEM-1型广谱β-内酰胺酶、CTX-M-3型ESBLs和MIR-3型AmpC酶,耐药现状严重,应采取积极有效的措施预防多药耐药菌株的播散与暴发流行。     

耐亚胺培南鲍曼不动杆菌碳青霉烯酶及整合子分布

目的 了解耐亚胺培南鲍曼不动杆菌碳青霉烯酶及整合子分布情况.方法 收集天津医科大学总医院2008年1月至2010年3月期间,103株亚胺培南耐药鲍曼不动杆菌临床标本.用Vitek-2系统鉴定细菌,并进行药敏试验,通过改良Hodge试验、改良三维试验和2-巯基丙酸协同试验初筛碳青霉烯酶,多重PCR同时检测4种OXA型碳青霉烯酶基因、2种金属酶基因及整合酶基因,对整合子可变区进行PCR检测及序列分析.结果 103株鲍曼不动杆菌中,改良Hodge试验检出碳青霉烯酶阳性75株(72.8%),改良三维试验检出产碳青霉烯酶菌株80株(77.7%),未检出产金属酶菌株.PCR检出blaOXA-51-like+bsaOXA-23-like+int11基因84株,blaOxA-51-like+blaOXA-23-like阳性5株,blaOXA-51-like+intll阳性8株,blaOXA-51-like+blaOXA-24-like阳性2株,仅blaOXA-51-like阳性4株,blaOXA-58-like、金属酶基因(IMP-1、VIM-2)及Ⅱ类整合酶基因(intI2)均阴性.89株(96.7%)Ⅰ类整合酶阳性株均扩增出可变区,检出2种耐药基因盒组合形式:aacA4-catB8-aadAl(2 300 bp)81株,aacCl-orfX-orfX-orfX'-aadAla(3 000 bp)8株.结论 鲍曼不动杆菌对碳青霉烯类耐药及多重耐药主要与其携带的OXA-23型碳青霉烯酶和Ⅰ类整合子有关.

Abstract：

Objective To investigate the carbapenemases and integrons in imipenem-resistant Acinetobacter baumannii. Methods One hundred and three Acinetobacter baumannii were collected from Janurary 2008 to March 2010 in Tianjin Medical University General Hospital. The identification of strains and antimicrobial susceptibility test were performed by using Vitek-2 compact automatic system. Isolates of imipenem-resistant A. baumannii were screened for carbapenemases by modified Hodge test, improved threedimensional test and 2-mercaptopropionic acid synergy test. Isolates were then subjected to the multiplex PCR targeting genes encoding for OXA type carbapenemases, metallo-β-lactamases (MBLs) and integrases. The variable regions of integrons were amplificated and sequenced. Results Among the 103 isolates, 75 (72. 8% ) demonstrated positive in the modified Hodge test, 80 (77.7%)were positive in the improved three-dimensional test. No MBLs was found in the 2-mercaptopropionic acid synergy test. Eightyfour isolates were positive for blaOXA-51-like, blaOXA-23-like, and intI1; five were positive for blaOXA-51-like and blaOXA-23-like ;eight were positive for blaOXA-51-like and int11 ;two were positive for blaOXA-51-like and blaOXA-24-like ;four were only found positive for blaOXA-51-like. The blaOXA-58-like, IMP-1, VIM-2 and intI2 genes were all negative. Eighty-nine(96. 7% )of the intI1 positive strains owned the variable region. Two different cassettes arrangements were identified within class 1 integrons:81 isolates harbored aacA4-catB8-aadAI (2 300 bp) and 8 harbored aacCl-orX-orfX-orX'-aadAla (3 000 bp ) . Conclusion The presence of OXA-23 carbapenermase and class Ⅰ integrons are correlated with Acinetobacter baumannii resistant to carbapenems and multi-drug resistance.     

耐亚胺培南鲍曼不动杆菌碳青霉烯酶及整合子分布

Objective To investigate the carbapenemases and integrons in imipenem-resistant Acinetobacter baumannii. Methods One hundred and three Acinetobacter baumannii were collected from Janurary 2008 to March 2010 in Tianjin Medical University General Hospital. The identification of strains and antimicrobial susceptibility test were performed by using Vitek-2 compact automatic system. Isolates of imipenem-resistant A. baumannii were screened for carbapenemases by modified Hodge test, improved threedimensional test and 2-mercaptopropionic acid synergy test. Isolates were then subjected to the multiplex PCR targeting genes encoding for OXA type carbapenemases, metallo-β-lactamases (MBLs) and integrases. The variable regions of integrons were amplificated and sequenced. Results Among the 103 isolates, 75 (72. 8% ) demonstrated positive in the modified Hodge test, 80 (77.7%)were positive in the improved three-dimensional test. No MBLs was found in the 2-mercaptopropionic acid synergy test. Eightyfour isolates were positive for blaOXA-51-like, blaOXA-23-like, and intI1; five were positive for blaOXA-51-like and blaOXA-23-like ;eight were positive for blaOXA-51-like and int11 ;two were positive for blaOXA-51-like and blaOXA-24-like ;four were only found positive for blaOXA-51-like. The blaOXA-58-like, IMP-1, VIM-2 and intI2 genes were all negative. Eighty-nine(96. 7% )of the intI1 positive strains owned the variable region. Two different cassettes arrangements were identified within class 1 integrons:81 isolates harbored aacA4-catB8-aadAI (2 300 bp) and 8 harbored aacCl-orX-orfX-orX'-aadAla (3 000 bp ) . Conclusion The presence of OXA-23 carbapenermase and class Ⅰ integrons are correlated with Acinetobacter baumannii resistant to carbapenems and multi-drug resistance.     

耐亚胺培南鲍曼不动杆菌碳青霉烯酶及整合子分布

Objective To investigate the carbapenemases and integrons in imipenem-resistant Acinetobacter baumannii. Methods One hundred and three Acinetobacter baumannii were collected from Janurary 2008 to March 2010 in Tianjin Medical University General Hospital. The identification of strains and antimicrobial susceptibility test were performed by using Vitek-2 compact automatic system. Isolates of imipenem-resistant A. baumannii were screened for carbapenemases by modified Hodge test, improved threedimensional test and 2-mercaptopropionic acid synergy test. Isolates were then subjected to the multiplex PCR targeting genes encoding for OXA type carbapenemases, metallo-β-lactamases (MBLs) and integrases. The variable regions of integrons were amplificated and sequenced. Results Among the 103 isolates, 75 (72. 8% ) demonstrated positive in the modified Hodge test, 80 (77.7%)were positive in the improved three-dimensional test. No MBLs was found in the 2-mercaptopropionic acid synergy test. Eightyfour isolates were positive for blaOXA-51-like, blaOXA-23-like, and intI1; five were positive for blaOXA-51-like and blaOXA-23-like ;eight were positive for blaOXA-51-like and int11 ;two were positive for blaOXA-51-like and blaOXA-24-like ;four were only found positive for blaOXA-51-like. The blaOXA-58-like, IMP-1, VIM-2 and intI2 genes were all negative. Eighty-nine(96. 7% )of the intI1 positive strains owned the variable region. Two different cassettes arrangements were identified within class 1 integrons:81 isolates harbored aacA4-catB8-aadAI (2 300 bp) and 8 harbored aacCl-orX-orfX-orX'-aadAla (3 000 bp ) . Conclusion The presence of OXA-23 carbapenermase and class Ⅰ integrons are correlated with Acinetobacter baumannii resistant to carbapenems and multi-drug resistance.     

南宁地区某院碳青霉烯类耐药肺炎克雷伯菌碳青霉烯酶表型与基因型检测

目的 了解南宁地区某院碳青霉烯类耐药肺炎克雷伯菌(CRKP)的耐药性及碳青霉烯酶产生情况,为CRKP感染防控提供依据。方法 收集2021年1月至2022年2月临床分离的CRKP共46株,用Phoenix M50全自动微生物鉴定药敏分析仪进行药敏试验,采用碳青霉烯酶抑制剂增强试验进行碳青霉烯酶表型筛选,用PCR扩增碳青霉烯酶耐药基因。结果 46株CRKP对厄他培南100%耐药,对亚胺培南和美罗培南的耐药率分别为76.1%和78.3%,对除氨曲南外的其他β-内酰胺类药物的耐药率均为100%,对替加环素耐药率为0,对多黏菌素B(4.3%)及阿米卡星(32.6%)耐药率较低;碳青霉烯酶表型筛选试验检出单产A类碳青霉烯酶菌株33株(71.7%),单产B类金属β-内酰胺酶9株(19.6%),单产D类OXA-48型碳青霉烯酶2株(4.3%),同时产A类和B类碳青霉烯酶2株(4.3%);46株CRKP均检出碳青霉烯酶耐药基因,其中,33株(71.7%)仅携带KPC-2基因,7株(15.2%)仅携带NDM-1基因,2株(4.3%)仅携带VIM-1基因,2株(4.3%)仅携带OXA-48基因,2株(4.3...     

耐亚胺培南鲍氏不动杆菌β-内酰胺酶基因型研究

目的探讨住院患者临床分离的耐亚胺培南鲍氏不动杆菌的耐药性及β-内酰胺酶基因型,为临床合理用药及医院感染控制提供依据。方法 PCR方法检测54株鲍氏不动杆菌的10种β-内酰胺酶耐药基因(blaOXA-23、blaOXA-24、blaOXA-51、blaOXA-58、blaVI M-2、blaI MP-1、ampC、blaDHA、blaTEM、blaSHV)并测序。结果鲍氏不动杆菌对大多数抗菌药物耐药率77.0%,对头孢哌酮/舒巴坦的耐药率最低,为24.1%;54株菌中均检出blaOXA-51、ampC、blaTEM基因(100.0%),blaOXA-23阳性44株(81.5%),blaOXA-24阳性2株(3.7%),测序证实为blaOXA-72,其余基因均阴性。结论耐亚胺培南鲍氏不动杆菌多药耐药现象严重,blaOXA-23、blaOXA-51、ampC和blaTEM基因携带率高。     

亚胺培南耐药鲍氏不动杆菌AmpC酶、ESBLs及金属酶检测和耐药分析

目的 分析我院亚胺培南耐药鲍氏不动杆菌(IRABA)临床分离株头孢菌素酶(AmpC酶)、超广谱β-内酰胺酶(ESBLs)和金属β-内酰胺酶(MBLs)的产生情况及其耐药特点.方法 应用VITEK-2全自动细菌鉴定仪进行细菌鉴定和药物敏感试验,采用改良三维试验方法同时检测2008年1月-2009年9月我院临床分离的63株IRABA的ESBLs和AmpC酶,2-巯基丙酸协同试验检测MBLs.结果 63株IRABA中,45株(71.4 %)AmpC酶阳性,13株(20.6 %)ESBLs阳性,其中8株(12.7 %)同时产AmpC酶和ESBLs,未检出产MBLs 菌株.AmpC酶阳性菌对12种抗生素的耐药率明显高于AmpC酶阴性菌,差异均有统计学意义(P＜0.05).结论 本组IRABA主要产AmpC酶,且多重耐药现象严重.     

Mohnarin 2008年度报告:腹腔感染病原菌分布及耐药监测

目的 了解2008年度我国腹腔感染细菌分布及耐药状况.方法 采用纸片法、MIC法或E-test法,使用WHONET5.4软件进行分析,对卫生部全国细菌耐药性监测网(Mohnarin)所属89家三级甲等医院2008年1月1日-2008年12月31日从腹腔感染标本中分离的菌株进行分析.结果 共分离菌株1405株,其中革兰阳性菌582株(41.4%),革兰阴性菌823(58.6%)株.分离率最高的前5位病原菌为大肠埃希菌(23%)、屎肠球菌(7.6%)、铜绿假单胞菌(7.3%)、金黄色葡萄球菌(7.1%)和表皮葡萄球菌(6.8%).大肠埃希菌和肺炎克雷伯菌对氟喹诺酮类的耐药率分别为77%与46.7%,ESBLs阳性检出率分别为47.1%和35.5%.发现1株万古霉素耐药粪肠球菌(VRE),粪肠球菌对替考拉宁耐药率为1.8%,屎肠球菌对万古霉素中介率为1.4%.耐甲氧西林金黄色葡萄球菌(MRSA)与凝固酶阴性葡萄球菌(MRCNS)的检出率分别为80.0%与74.3%,未检测到万古霉素耐药株,金黄色葡萄球菌和表皮葡萄球菌对替考拉宁的中介率分别为有1.8%与2.3%.铜绿假单胞菌和鲍曼不动杆菌对亚胺培南的耐药率分别为28.8%和52.6%.结论 我国腹腔感染主要致病菌以大肠埃希菌为代表的革兰阴性杆菌为主,肠球菌等革兰阳性菌所占比例有所增多;细菌耐药性仍呈上升趋势,应采取有效措施,控制耐药菌增长与传播.     

耐亚胺培南鲍曼不动杆菌碳青霉烯酶基因型及插入序列ISA ba1研究

目的：检测耐亚胺培南鲍曼不动杆菌的碳青霉烯酶基因型及其基因周围环境。 方法：对101株耐亚胺培南鲍曼不动杆菌进行药物敏感试验,头孢他啶与2-巯基丙酸协同试验筛选金属酶,多重PCR同时检测6种碳青霉烯酶耐药基因,对部分阳性产物进行测序比对,同时分析碳青霉烯酶基因上游插入序列。 结果：协同试验未检出产金属酶菌株。所有菌株都携带OXA-51-like基因,87株（86.1%）OXA-23-like基因阳性,2株OXA-24-like基因阳性,OXA-58-like基因与金属酶基因全为阴性。85株OXA-23-like基因上游检测到插入序列ISA ba1,OXA-51-like基因上游未检测到ISA ba1。 结论：OXA-23和OXA-51组β-内酰胺酶基因是本组鲍曼不动杆菌最主要的碳青霉烯酶基因型,OXA-23组碳青霉烯酶基因与插入序列 ISA ba1关系密切。