耐碳青霉烯类肺炎克雷伯菌的耐药基因分析

目的 了解铜陵市人民医院分离的碳青霉烯类耐药肺炎克雷伯菌（CRKP）的耐药基因型。方法 收集2011年5月至2016年8月铜陵市人民医院临床标本中分离的CRKP,采用VITEK-2 Compact全自动微生物鉴定仪进行鉴定,改良Hodge试验检测碳青霉烯酶表型,聚合酶链反应（PCR）检测碳青霉烯酶基因（bla_KPC、bla_IMP、bla_VIM、bla_NDM和bla_OXA-48）,并对各碳青霉烯酶基因阳性扩增产物进行基因测序。结果 共收集CRKP 90株,其中改良Hodge试验阳性84株（93.3%）,51株（56.7%）携带bla_KPC-2基因,2株（2.2%）携带bla_IMP-4基因,1株（1.1%）携带bla_VIM-1基因。结论 该院肺炎克雷伯菌对碳青霉烯类抗菌药物的主要耐药机制是产KPC-2型碳青霉烯酶。     

碳青霉烯类抗菌药物敏感性下降肠杆菌科细菌耐药基因型研究

目的 研究碳青霉烯类抗菌药物敏感性下降肠杆菌科细菌的耐药情况及产碳青霉烯酶基因型。方法 对临床分离到非重复的36株耐碳青霉烯类肠杆菌科细菌,应用改良Hodge试验进行产碳青霉烯酶的表型确证,PCR扩增技术分析产碳青霉烯酶基因型。结果 药敏试验显示36株碳青霉烯类耐药肠杆菌科细菌具有对第3,4代头孢菌素、碳青霉烯类、氟喹诺酮类和酶抑制剂复合制剂等多重耐药。36株菌株中有16株改良Hodge试验阳性;PCR结果10株细菌携带bla_KPC,未检出bla_IMP、bla_VIM、bla_GIM、bla_SIM、bla_NDM-1基因条带。结论 产KPC酶是台州医院碳青霉烯类抗菌药物敏感性下降肠杆菌科细菌的主要耐药机制,其中KPC是主要基因型。     

安徽省某三甲医院铜绿假单胞菌分布及耐药特点研究

目的 探讨安徽某三甲医院临床分离的铜绿假单胞菌（PA）的临床分布及耐药相关特点。方法 收集安徽省某三甲医院2015年8月至2017年9月临床分离的1 857株无重复PA的时间、科室以及菌株标本来源分布特点,并进行药敏分析,对耐碳青酶烯类抗菌药物的PA进行耐药相关基因的扩增。结果 ICU和呼吸内科为PA分离最多的科室,标本来源最多为痰液1 261株（67.91%）。药敏结果提示,PA对头孢吡肟和阿米卡星的敏感率较高,分别达到了66.72%和78.08%。PA对亚胺培南的耐药菌株数为607株（耐药率32.69%）,对这607株耐药菌株检出携带bla_TEM34株、bla_PER41株、bla_VEB7株、bla_OXA63株。检出携带VIM基因121株,IMP基因125株,SPM基因65株。其中有98株携带2种耐药基因。测出孔蛋白基因缺失417株。结论 PA感染部位以呼吸道最为多见,破损皮肤、血液和泌尿系感染亦较多。PA耐药机制比较复杂多样,外膜蛋白缺失为耐碳青霉烯类PA的主要耐药机制。     

碳青霉烯类耐药肺炎克雷伯菌临床分离株中质粒介导的喹诺酮类耐药基因检测

目的：探讨质粒介导的喹诺酮类耐药（PMQR）基因在碳青霉烯类耐药肺炎克雷伯菌（CRKP）临床分离株中的分布情况。方法：收集CRKP29株,聚合酶链反应（PCR）扩增并确定产物基因型。结果：CRKP中PMQR基因检出率为48．3％（14／29）,其中qnrB5株,包括qnrB21株、qnrB43株、qnrB101株;qnrS 5株,均为qnrS1;1株同时携带qnrS1和qnrB4;有3株携带aac（6′）-Ib-cr基因。所有PMQR基因阳性菌株均同时携带β-内酰胺酶基因,其中8株同时携带碳青霉烯酶基因,占57．1％（8／14）,以blaKPC-2（4／14）及blaNDM-1（3／14）为主。结论：PMQR基因在临床分离的CRKP中较为普遍,以qnr基因为主,且qnr阳性菌株碳青霉烯酶基因携带率较高,均为多重耐药株。     

碳青霉烯耐药肺炎克雷伯菌在某院的耐药流行分析

目的:了解我院碳青霉烯耐药肺炎克雷伯菌(CRKP)耐药流行情况.方法:收集佳木斯大学附属第一医院CRKP,VITEK 2 Compact药敏鉴定,K-B法复核;mCIM初步鉴定碳青霉烯酶,PCR扩增相关耐药基因进行验证.结果:31株CRKP对亚胺培南、美罗培南及哌拉西林/他唑巴坦耐药率较高,对左氧氟沙星及阿米卡星耐药率较低;31株CRKP经表型鉴定有30株产碳青霉烯酶;30株CRKP全部携带KPC-2型碳青霉烯酶基因,1株携带NDM型,未检出OXA-48型,31株CRKP菌株12株分离自ICU病房.结论:CRKP以产KPC-2型酶为主,在ICU病房CRKP易传播流行.     

2018—2019年北京市海淀医院多重耐药鲍曼不动杆菌临床感染特点及耐药性分析

目的 分析北京市海淀医院多重耐药鲍曼不动杆菌（multidrug-resistant Acinetobacter baumannii,MDR-AB）临床感染的特点及耐药性,为临床用药提供一定的理论依据。方法 将北京市海淀医院2018年10月—2019年10月分离的178株鲍曼不动杆菌（Acinetobacter baumannii）作为研究对象,对其相关临床资料及体外药物敏感性试验结果进行分析。结果 鲍曼不动杆菌多重耐药率为46.6%,且97.6% MDR-AB为耐碳青霉烯鲍曼不动杆菌（CR-AB）。MDR-AB主要分离自高龄（>60岁）患者（86.7%）和重症监护室（ICU）患者（65.1%）,且86.7% MDR-AB分离自痰液标本。MDR-AB对各种常用抗菌药物的耐药率明显高于普通鲍曼不动杆菌,差异具有统计学意义（P<0.05）;MDR-AB中同时耐碳青霉烯类、氟喹诺酮类、抗铜绿假单胞菌青霉素加酶抑制剂类、广谱头孢菌素类、氨基糖苷类、四环素类等抗菌药物的菌株的占比最高（39.8%）。结论 高龄和ICU患者是MDR-AB的主要易感人群,MDR-AB对各种常用抗菌药物的耐药率明显高于普通鲍曼不动杆菌,替加环素对MDR-AB的耐药率相对低于其他抗菌药物,临床应合理使用抗菌药防止MDR-AB的产生和传播。     

2019—2021年天津市宝坻区人民医院住院患者多重耐药菌检出及耐药分析

目的 探讨2019—2021年天津市宝坻区人民医院住院患者多重耐药菌（MDRO）检出及耐药分析,为临床抗菌药物的合理应用提供依据。方法 收集2019年1月—2021年12月天津市宝坻区人民医院住院患者送检标本分离的MDRO,排除同一患者同一部位分离的重复菌株。采用法国生物梅里埃公司VITEK-2 Compact型全自动微生物鉴定与药敏分析仪进行病原菌鉴定和药敏试验。对临床使用的3类或3类以上抗菌药物同时呈现耐药的细菌定义为MDRO并进行耐药分析。结果 检出多重耐药菌1 083株,其中产超广谱β-内酰胺酶（ESBLs）大肠埃希菌645株（59.56%）、产ESBLs肺炎克雷伯菌144株（13.3%）、多重耐药鲍曼不动杆菌（MDRAB）140株（12.93%）、耐甲氧西林金黄色葡萄球菌（MRSA）79株（7.29%）、多重耐药铜绿假单胞菌（MDRPA）54株（4.99%）、耐碳青霉烯的肠杆菌（CRE）21株（1.94%）。2019—2021年,MDRAB、MDRPA和CRE的检出率比较差异有统计学意义（P＜0.05）;组间比较,MDRAB的检出率2021年高于2020年（P＜0.05）,MDRPA和CRE的检出率2021年高于2019年（P＜0.05）。标本主要来源于痰液、尿液、分泌物,占比分别为37.12%,23.45%,18.01%。3年间检出MDRO最高的科室为ICU,共167株（15.42%）。产ESBLs大肠埃希菌对氨苄西林、头孢唑林、头孢曲松、头孢呋辛钠、哌拉西林的耐药率较高,均在90%以上,对美罗培南、亚胺培南、阿米卡星、头孢替坦、哌拉西林/他唑巴坦敏感,敏感率在90%以上;产ESBLs肺炎克雷伯菌对氨苄西林、头孢呋辛钠、头孢曲松、哌拉西林的耐药率较高,均在90%以上,对美罗培南、亚胺培南、头孢替坦和阿米卡星敏感,敏感率在90%以上;MDRAB仅对阿米卡星较敏感,敏感率在90%以上,对大部分抗菌药耐药率均较高;MDRPA对阿米卡星的敏感率为50%,对大部分抗菌药耐药率均较高。MRSA对利福平、复方新诺明、庆大霉素、环丙沙星、左氧氟沙星、莫西沙星的耐药率在10%～20%,尚未发现对万古霉素、利奈唑胺、替加环素耐药的菌株。结论 天津市宝坻区人民医院分离的MDRO对抗菌药物有不同程度的耐药,加强病原学检查及耐药监测有助于临床合理选择抗菌药的种类和剂量,减少多重耐药菌的发生。     

耐碳青霉烯类抗生素肺炎克雷伯菌种群结构和耐药机制研究

耐碳青霉烯类抗生素肺炎克雷伯菌(carbapenem-resistant Klebsiella pneumoniae, CRKP)是临床常见的耐药菌之一。本研究对88株全国49家医院收集的CRKP菌株进行碳青霉烯类耐药基因检测,其中65株(73.9%)检出blaKPC类基因(64株检出blaKPC-2、1株检出blaKPC-3)、9株(10.2%)检出blaNDM类基因(均为blaNDM-1)、7株(8.0%)检出blaIMP类基因(均为blaIMP-4)。通过多位点序列分型(multi-locus sequence typing, MLST)将88株CRKP分为25个MLST型,其中ST11型为优势型别,包含48株菌。88株CRKP通过脉冲场凝胶电泳(pulsed field gel electrophoresis, PFGE)分为79个PFGE型,呈现高度多态性。本研究揭示了我国blaKPC-2阳性CRKP菌株存在克隆化现象,存在ST11型流行克隆;而blaNDM-1和blaIMP-4阳性CRKP菌株分子型别多态性大,还没形成流行克隆。需要密切监测并采取措施控制携带blaKPC-2基因的ST11型CRKP的传播扩散。     

儿童肺炎患者碳青霉烯耐药肠杆菌的临床特征分析

目的：探讨儿童肺炎碳青霉烯耐药肠杆菌耐药机制和临床传播特征,分析医院感染防控措施及经验。方法：收集江苏省徐州市中心医院2017年8月至2019年10月收治的216例儿童肺炎患者中分离的46株非重复碳青霉烯耐药肠杆菌科细菌,并进行菌株鉴定、药敏试验、基因检测、同源性、传播特征及相关临床资料分析,根据脉冲场凝胶电泳（PFGE）分型将肺炎克雷伯菌携带blaNDM-1基因的儿童肺炎患者分为A型组和非A型组,并对相关数据进行统计学分析。结果：儿童肺炎患者碳青霉烯耐药肠杆菌主要包括肺炎克雷伯菌25株（54.35%）、大肠埃希菌7株（15.22%）、阴沟肠杆菌4株（8.70%）、产酸克雷伯菌4株（8.70%）、弗劳地枸橼酸杆菌3株（6.52%）及粘质沙雷菌3株（6.52%）。碳青霉烯耐药肠杆菌对阿米卡星敏感率为86.10%,对头孢唑林、头孢他啶、头孢曲松、厄他培南、美罗培南、亚胺培南和头孢哌酮/舒巴坦耐药率分别为100.00%、100.00%、100.00%、100.00%、97.70%、95.30%及95.30%。碳青霉烯耐药肠杆菌经改良Hodge试验和乙二胺四乙酸（EDTA）协同试验阳性率分别为58.70%及36.97%,聚合酶链式反应（PCR）检测携带blaKPC-2基因者27株（58.70%）,携带blaNDM-1基因者16株（34.78%）,携带blaIMP-4基因者1株（2.17%）。13株携带碳青霉烯耐药blaNDM-1基因的肺炎克雷伯菌PFGE分型为A型7株,B型2株,C、D、E、F型各1株。A型组和非A型组患儿重症监护室（ICU）住院史和住院时间≥30 d比较差异有统计意义（P<0.05）。结论：儿童肺炎患者碳青霉烯耐药肠杆菌呈多重耐药,耐药机制主要缘于碳青霉烯酶基因克隆传播,且与患儿ICU住院史和住院时间延长有关,临床应加强医院感染防控措施以预防耐药菌传播。     

2015—2019年天津市胸科医院血流感染多重耐药菌的菌株变迁及危险因素相关性分析

目的 分析天津市胸科医院血流感染多重耐药菌的菌株流行情况和危险因素,为其合理治疗及控制提供循证学依据。方法 收集2015年1月1日—2019年12月31日天津市胸科医院全血标本分离出的菌株,分析各类多重耐药菌株变迁趋势、耐药性,以及医院获得性血流感染的危险因素。结果 5年间全血标本共分离菌株1 207株,检出多重耐药菌134株,检出率11.10%。多重耐药菌株总体数量以及产超广谱β内酰胺酶（ESBLs）肠杆菌、耐碳青霉烯类鲍曼不动菌（CRAB）变化趋势均不大。产ESBLs细菌对头孢菌素类、喹诺酮类、复方新诺明等耐药严重,CRAB对除替加环素、米诺环素、粘菌素外的抗菌药物耐药率均较高。与对照组相比,糖尿病（OR=2.202,P=0.005）、低蛋白血症（OR=9.502,P=0.006）、机械通气（OR=0.051,P=0.002）、行外科手术（OR=8.056,P=0.012）、入住ICU（OR=5.200,P=0.035）是观察组患者发生多重耐药菌感染的独立危险因素。结论 临床医生应严格遵照抗菌药物分级管理制度,合理应用抗菌药,同时,密切关注菌株流行情况,重视感染的早期防控,积极预防和控制多重耐药菌的产生和流行。     

Molecular characterization of novel sequence type of carbapenem-resistant New Delhi metallo-β-lactamase-1-producing Klebsiella pneumoniae in the neonatal intensive care unit of an Indian hospital

Emergence of multi-drug resistance, especially carbapenem-resistant Klebsiella pneumoniae (CRKP) is a major threat to public health. The aim of this study was to characterize CRKP isolates from infants admitted to the Neonatal Intensive Care Unit (NICU) to find the clonal outbreak of New Delhi metallo-β-lactamase (NDM) producers. In this study 17 CRKP isolates were analysed. Antimicrobial susceptibility of the isolates was determined by the disc diffusion and micro-dilution method. Carba-NP test and double-disk synergy test (DDST) were performed for the detection of carbapenemase and metallo-β-lactamase-producing K. pneumoniae. Antibiotic-resistant markers were detected by polymerase chain reaction (PCR) followed by sequencing. Clonal relatedness of the isolates was checked by multi-locus sequence typing. Conjugation experiments were performed to determine the transferability of the plasmids. All 17 CKRP isolates were found to carry bla_NDM (13 bla_NDM-1, 1 bla_NDM-4 and 3 bla_NDM-5), seven isolates carried bla_OXA-48, 13 isolates had bla_CTX-M-15, seven isolates carried bla_CMY-1 and five isolates were found to carry bla_SHV-1 on conjugative plasmids of different types (IncFIA, IncFIB, IncFIIAs, IncFIC, IncA/C, IncF, IncK, IncX, IncW and IncY). Of six different sequence types (STs) identified, ST3344 was detected as a novel ST in two K. pneumoniae isolates. Genetic environment analysis revealed ISAba125 and bleomycin genes flanking to all bla_NDM variants. This is the first report of novel ST3344 in two NDM-1-producing K. pneumoniae isolates from neonates admitted to the NICU of a North Indian Hospital. This study is provides understanding of the genetic features of this newly emerged strain type.     

High-level and novel mechanisms of carbapenem resistance in Gram-negative bacteria from tertiary hospitals in Nigeria

To determine the occurrence and molecular basis of carbapenem resistance in Gram-negative bacteria from tertiary hospitals in Nigeria, 182 non-duplicate Gram-negative bacterial isolates were investigated for antimicrobial susceptibility, presence of carbapenemases (tested phenotypically and genotypically), random amplified polymorphic DNA (RAPD) typing, plasmid sizing and replicon typing. Minimum inhibitory concentrations of carbapenems showed a high degree of resistance, with 67 isolates (36.8%) being resistant to all carbapenems, of which 40 (59.7%) produced enzymes able to hydrolyse imipenem. PCR and sequencing identified only 10 isolates (5.5%) carrying known carbapenemase genes, including bla_NDM, bla_VIM and bla_GES. The majority of phenotypically carbapenem-resistant and carbapenemase-producing isolates did not carry a known carbapenemase gene. Transconjugant or transformant plasmid sizes were estimated to be 115 kb for bla_NDM- and 93 kb for bla_VIM-carrying plasmids. These plasmids were untypeable for replicon/incompatibility and transferred various other genes including plasmid-mediated quinolone resistance (PMQR) genes and bla_CTX-M-15. Typing showed that the isolates in this study were not clonally related. There is a high level of carbapenem resistance in Nigeria. As well as the globally relevant carbapenemases (bla_NDM, bla_VIM and bla_GES), there are other unknown gene(s) or variant(s) in circulation able to hydrolyse carbapenems and confer high-level resistance.     

Genotypes,carbapenemase carriage,integron diversity and oprD alterations among carbapenem-resistant Pseudomonas aeruginosa from Russia

Pseudomonas aeruginosa is a serious opportunistic pathogen demonstrating a high level of resistance to many groups of antibiotics, including carbapenems. This study aimed to characterise the molecular epidemiology and prevalence of mobile genetic elements associated with resistance to carbapenems among P. aeruginosa (CRPA) clinical isolates. Among 145 carbapenem-resistant P. aeruginosa isolates, 34 different sequence types (STs) were detected; the six most common STs were ST654 (24%), ST235 (24%), ST111 (8%), ST446 (6%), ST357 (5%) and ST2592 (a novel single-locus variant of ST357) (4%). A carbapenemase gene was found in 94 isolates (64.8%). The bla_VIM-2 gene was harboured by 64 isolates (44.1%) restricted to ST111, ST235 and ST654, and the bla_GES-type and bla_OXA-10 group genes were each detected in 15 isolates (10.3%); none of other tested carbapenemase genes, including bla_IMP, bla_NDM and bla_GIM, were detected. Among the bla_VIM-2-positive isolates, five types of bla_VIM-2-containing integrons were discovered, including In56, In559, In59-like, In59 and In249. The oprD gene was disrupted by an insertion sequence (IS) in 15.9% of isolates. Overall, five types of IS elements were found (ISPsme1, ISPa1328, ISPa26, ISPst2 and ISPa195). Observed rearrangements within variable regions of bla_VIM-2-carrying integrons in conjunction with the discovery of a novel type of oprD-disrupting IS element illustrate the ongoing evolution of CRPA a, which warrants further investigation.     

贵阳某医院耐碳青霉烯类肺炎克雷伯菌的分子流行病学分析

目的 研究耐碳青霉烯类肺炎克雷伯菌(carbapenem resistant Klebsiella pneumoniae, CRKP)的耐药性、耐药基因与同源性，为临床用药与院感控制提供依据。方法 收集贵州省人民医院2016年5月-2017年2月临床上分离的50株CRKP，检测其对19种抗菌药的药物敏感性。PCR法扩增碳青霉烯酶基因(blaKPC、blaIMP、blaVIM、blaOXA和blaNDM-1)并对扩增阳性产物进行测序，所得序列与GenBank数据库进行比对，确定耐药基因分型。采用ERIC-PCR法进行同源性检测。结果 50株CRKP均为多重耐药菌。19种抗菌药物中，耐药率低于50%的抗菌药物有多黏菌素0、替加环素4%、米诺环素20%、四环素38%。对复方磺胺甲噁唑的耐药率为60%，对碳青霉烯类、头孢菌素、氨曲南、含酶抑制剂、以及喹诺酮类、氨基糖苷类的耐药率为84%~100%。50株CRKP中，48株(96%)检出碳青霉烯酶基因，其中41株(82%)blaKPC-2、3株(6%)blaIMP-8和4株(8%)blaNDM-1。41株检出KPC-2型碳青霉烯酶的CRKP分为6个基因型(A-F型)，其中A型18株、B型6株、C型12株、D型3株、E型、F型各1株。结论 CRKP的耐药率高，主要耐药机制是产KPC-2型碳青霉烯酶，其次是产NDM-1、IMP-8型碳青霉烯酶。CRKP存在科室间、科室内的克隆传播，应加强对CRKP的监测和院感控制。     

Confronting Ceftolozane-Tazobactam Susceptibility in Multidrug-Resistant Enterobacterales Isolates and Whole-Genome Sequencing Results (STEP Study)

Ceftolozane-tazobactam (C/T) is frequently used for infections caused by multidrug-resistant (MDR)-Enterobacterales isolates. Whole-genome sequencing (WGS, Illumina-Hiseq 4000/NovaSeq 6000, OGC, UK) was used to study the population structure, the resistome and the virulome of C/T-susceptible and -resistant MDR Escherichia spp. (n=30) and Klebsiella spp. (n=78) isolates, recovered from lower respiratory, intra-abdominal and urinary tract infections of ICU patients from 11 Portuguese Hospitals (STEP study, 2017-2018). Minimum inhibitory concentrations (MICs) were determined (ISO-broth microdilution, breakpoints EUCAST-2020). In Escherichia spp., a weak concordance between the phenotypic and the WGS method (P=0.051) was observed in the carbapenemase detection (3/30) [bla_VIM-2 (2/3), bla_KPC-3 (1/3)]; VIM-2-Escherichia coli isolates were C/T-susceptible and only the KPC-3-Escherichia marmotae producer showed C/T-resistance. Overall, CTX-M-15-E. coli-ST131-O25:H4-H30-Rx (11/30) was the most frequent subclone, followed by CTX-M-27-E. coli-ST131-O25:H4-H30 (4/4). Moreover, a wide resistome and virulome were detected in all E. coli isolates. Among Klebsiella spp. isolates [K. pneumoniae (67/78), K. aerogenes (7/78), K. oxytoca (2/78), K. variicola (2/78)], concordance (P<0.001) was observed between the phenotypic and the genomic carbapenemase detection (21/78) [bla_KPC-3 (14/21), bla_OXA-48 (3/21), bla_OXA-181 (3/21)]. A high correlation between C/T-resistance and carbapenemase detection was established (P<0.05). Overall, a high clonal diversity was observed, mainly in KPC-3-producing K. pneumoniae isolates. An extensive resistome was detected in Klebsiella spp. isolates, whereas virulence determinants were mostly identified in carbapenemase producers (P<0.001). WGS is a powerful tool for typing characterization and microbiological study of MDR-Enterobacterales pathogens. Furthermore, carbapenemase genes are associated with C/T-resistance in Klebsiella spp., but other mechanisms might also be involved.     

Emergence of a ST307 clone carrying a novel insertion element MITEKpn1 in the mgrB gene among carbapenem-resistant Klebsiella pneumoniae from Moscow,Russia

Carbapenem-resistant Klebsiella pneumoniae (CRKP) represents a major nosocomial pathogen with only a few antimicrobial agents, including colistin, remaining active. However, the emergence of colistin-resistant (Col-R) isolates is compromising the activity of colistin. In this study, a collection of 159 CRKP recovered from three hospitals in Moscow (Russian Federation) was examined. The isolates demonstrated resistance to cephalosporins (100%), ciprofloxacin (92.5%), fosfomycin (90.1%), netilmicin (81.1%), gentamicin (84.3%) and amikacin (49.7%). The rate of colistin resistance (MIC > 2 mg/L by broth microdilution) was 44.7%; moreover, 6.7% of isolates were tigecycline-resistant. Among 18 sequence types (STs) discovered, isolates of five lineages including ST307 (n = 46; 28.9%), ST395 (n = 40; 25.2%), ST377 (n = 17; 10.7%), ST48 (n = 17; 10.7%) and ST23 (n = 16; 10.1%) dominated. Carriage of a bla_OXA-48-like carbapenemase gene was detected in 146 CRKP (91.8%); 11 (6.9%) and 2 (1.3%) isolates harboured bla_NDM-1 and bla_KPC-3, respectively. Among 71 Col-R isolates, colistin MICs ranged from 4 mg/L to >1024 mg/L (MIC_50/90, 2/512 mg/L). All Col-R isolates were mcr-1-negative. In 19 (26.8%) Col-R isolates, inactivation of mgrB by insertion sequences IS1A, IS1R, ISKpn14 and ISKpn26 and a novel miniature inverted-repeat transposable element (MITE) Kpn1 was observed. Carriage of MITEKpn1 was restricted to six ST307 isolates and affected mgrB at nucleotide position 75. mgrB deletion was observed in four (5.6%) Col-R isolates. Moreover, PmrA and/or PmrB were altered in three (4.5%) Col-R isolates with wild-type mgrB. Thus, bla_OXA-48-like-carrying Col-R ST307 K. pneumoniae is emerging as a dominant clone in Moscow.     

产KPC酶肺炎克雷伯菌耐碳青霉烯类药物的分子机制研究

摘要：目的 研究临床分离肺炎克雷伯菌对碳青霉烯类药物的分子耐药机制,为临床合理用药提供理论及实验依据。方 法 收集2020年1月-2020年12月皖南医学院弋矶山医院临床分离非重复肺炎克雷伯菌株923株,利用全自动微生物分析系统进 行菌种鉴定及药敏分析,并用16S rRNA PCR扩增产物测序验证菌种,K-B法复核碳青霉烯类药物耐药情况;胶体金法对耐碳青 霉烯类肺炎克雷伯菌(carbapenem-resistant Klebsiella pneumonia, CRKP)菌株进行碳青霉烯酶的表型检测,并用碳青霉烯酶PCR扩 增结果进行验证;同时利用全自动微生物分析系统对产KPC酶CRKP产超广谱β-内酰胺酶(extended-spectrum β-lactamases, ESBLs) 进行检测,并用ESBLs耐药相关基因PCR扩增结果进行验证;多位点序列分型技术(MLST)对产KPC酶CRKP进行序列分型 (ST)。 结果 923株肺炎克雷伯菌中256株(27.74%)为CRKP,其中183株携带blaKPC,ST分型为ST11型和ST12型,产KPC酶CRKP 携带3种ESBLs基因blaTEM-1、blaSHV-11和blaCTX-M-1。结论 CRKP产碳青霉烯酶以KPC酶型为主,blaKPC可合并3种ESBLs的产生。     

2016—2018年成都某院耐碳青霉烯肺炎克雷伯菌耐药变迁#br# 及耐药机制分析

目的 分析2016—2018年四川省中医医院临床分离的耐碳青霉烯肺炎克雷伯菌(carbapenem resistant Klebsiella pneumoniae, CRKP)的耐药性变迁及耐药机制。方法 收集本院临床分离的CRKP菌株,PCR扩增碳青霉烯酶基因A类(blaKPC、blaGES、blaSME、blaIMI和blaNMC),B类(blaNDM、blaVIM、blaIMP、blaSPM、blaGIM、blaSIM)和D类(blaOXA)。结果 近3年分离的CRKP对临床常用抗生素呈高水平耐药。经PCR扩增及测序确认,74株CRKP中,82.43%携带blaKPC-2型,10.81%携带blaNDM-1型,5.41%携带blaKPC-19型。结论 3年间本院分离的CRKP对临床常用抗生素呈高度耐药,菌株产blaKPC-2和blaNDM-1是本院CRKP最主要的耐药机制。