危重病房耐碳青霉烯酶鲍曼不动杆菌同源性研究

目的探讨杭州市第一医院危重病房耐碳青霉烯酶鲍曼不动杆菌之间的同源性,进行分子流行病学调查,旨在为制定预防和控制其院内感染的措施提供依据。方法收集该院危重病房2005年1月至12月分离到的34株亚胺培南耐药鲍曼不动杆菌。采用全自动微生物分析系统VITEK-AMS60对34株耐碳青霉烯酶鲍曼不动杆菌进行鉴定及药敏;用琼脂稀释法和E-test法测定14种抗菌药物的最低抑菌浓度(MIC),脉冲场凝胶电泳(PF-GE)分析其耐药株的同源性,对碳青霉烯类基因OXA-23型、OXA-24型、IMP型、VIM型基因进行PCR扩增及序列分析。结果PFGE发现34株鲍曼不动杆菌菌株为同一耐药克隆株,在危重病房呈爆发流行。所有对亚胺培南耐药鲍曼不动杆菌明确产OXA-23型碳青霉烯酶,未检出OXA-24、IMP、VIM基因型。34株菌株质粒提取未成功。结论该院同一个耐药克隆株在危重病房不同患者身上流行,可能与行气管插管、呼吸机、氧气湿化瓶、护士手操作有关。     

耐碳青霉烯类鲍曼不动杆菌OXA和NDM-1耐药基因的研究

目的检测江苏盛泽医院耐碳青霉烯类抗生素鲍曼不动杆菌的OXA和NDM-1耐药基因,分析耐碳青霉烯类抗菌药物的耐药机制。方法采用改良Hodge试验检测30株耐碳青霉烯类抗生素鲍曼不动杆菌产酶情况;用PCR的方法检测OXA-23、OXA-24、VIM、IMP和NDM-1碳青霉烯酶耐药基因。结果 30株分离菌中25株菌改良Hodge试验阳性,22株携带OXA-23型碳青霉烯酶耐药基因,未扩增出NDM-1碳青霉烯酶耐药基因。结论本院耐碳青霉烯类抗生素鲍曼不动杆菌的耐药机制主要是携带OXA-23型碳青霉烯酶基因。     

皖北地区耐碳青霉烯鲍曼不动杆菌产金属β-内酰胺酶检测

目的了解皖北地区ICU病房内耐碳青霉烯鲍曼不动杆菌产金属β-内酰胺酶（metallo-β-lactamase,MBL）情况。方法收集皖北地区3家教学医院ICU病房中不动杆菌,K-B纸片扩散法检测其对碳青霉烯类抗生素耐药情况;PCR法检测blaIMP、blaVIM等MBL基因。结果共收集35株耐亚胺培南、美罗培南非重复分离鲍曼不动杆菌菌株,其中9株（25.7%）金属酶初筛阳性;PCR检测5株（5/35,14.3%）产IMP型MBL,1株（1/35,2.9%）VIM型MBL。结论在本地区耐碳青霉烯鲍曼不动杆菌中首次发现IMP和VIM型金属酶,提示产金属酶机制参与本地区鲍曼不动杆菌对碳青霉烯耐药,值得进一步关注。     

鲍曼不动杆菌中OXA碳青霉烯酶的表型筛选与PCR检测

摘要：目的 了解OXA碳青霉烯酶在暨南大学附属第一医院耐亚胺培南鲍曼不动杆菌中的流行状况,完善OXA碳青霉烯酶的分子流行病学资料。方法 采用改良Hodge试验筛选产碳青霉烯酶菌株,多重PCR法检测OXA碳青霉烯酶的编码基因（blaOXA-23-like、blaOXA-24-like、blaOXA-58-like和blaOXA-143）,利用生物信息学的方法对OXA亚型进行比对分析并制作分子进化树。结果 在157株耐亚胺培南鲍曼不动杆菌中Hodge试验筛选出碳青霉烯酶表型阳性菌株141株,PCR检测结果显示有132株携带OXA-23编码基因,未检测到OXA-24-like、OXA-58-like和OXA-143亚型。结论 产OXA-23碳青霉烯酶是该院鲍曼不动杆菌对亚胺培南耐药的主要机制之一。     

鲍曼不动杆菌的耐药情况及碳青霉烯酶基因检测

了解佳木斯大学附属第一医院鲍曼不动杆菌耐药性及碳青霉烯酶包括苯唑西林酶和金属酶相关耐药基因分布情况,为临床抗菌药物的合理选择提供依据。2013年9月至2014年12月使用VITEK-II全自动微生物鉴定/药敏测试系统筛选出佳木斯大学附属第一医院临床标本鲍曼不动杆菌69株;采用多重PCR方法检测鲍曼不动杆菌携带的碳青霉烯酶相关耐药基因16SrRNA、OXA-23、OXA-24、OXA-51、OXA-58、IMP、VIM、SIM,并对耐药基因扩增的阳性产物进行DNA 序列分析。69株AB对亚胺培南、美洛培南的耐药率分别为36.2%、37.68%,对其他抗菌药物的耐药率均高于50%。6种耐药基因的检测结果为69株(100%)携带OXA-51基因,32株(46.4%)携带OXA-23基因,17株(24.6%)携带OXA-24基因,5株(7.2%)携带OXA 58基因,1株（1.4%）携带IMP基因。25株碳青霉烯类药物耐药鲍曼不动杆菌中,22株(88%) 携带OXA-23,1株(4%)携带OXA-58,10株(40%)携带OXA-24,6株（24%）同时携带OXA-23、OXA-24。 DNA序列分析结果显示：OXA-23、OXA-24、OXA-51、OXA-58分别与NCBI的序列同源性均为99%。产OXA-23型碳青霉烯酶可能是佳木斯大学附属第一医院鲍曼不动杆菌对碳青霉烯酶类抗菌药物耐药的主要原因,另外佳木斯大学附属第一医院存在OXA-24型耐药基因鲍曼不动杆菌的区域性流行。     

426株鲍曼不动杆菌的耐药性分析与OXA-23型碳青霉烯酶检测

目的 了解暨南大学附属第一医院2009年至2011年鲍曼不动杆菌的分布特点和耐药状况,为临床合理使用抗生素提供依据,同时研究广州地区亚胺培南耐药鲍曼不动杆菌中OXA-23型碳青霉烯酶的分子流行病学特征.方法 利用梅里埃VITEK-2 Compact微生物分析仪鉴定细菌,K-B法进行药敏试验,采用WHONET 5.6软件统计分析药敏结果,PCR检测OXA-23型碳青霉烯酶的编码基因.结果 2009年至2011年临床分离出426株鲍曼不动杆菌,主要分离自呼吸科病房(119株,占27.9％)和ICU病房(107株,占25.1％),标本类型以痰液为主(361株,占84.7％),鲍曼不动杆菌对12种抗生素的耐药率总体呈逐年上升趋势,对亚胺培南的耐药率从13.2％上升到39.3％,在124株亚胺培南耐药鲍曼不动杆菌中PCR检出98株OXA-23型碳青霉烯酶阳性菌株.结论 鲍曼不动杆菌对各种抗菌药物的耐药性逐年增强,产OXA-23型碳青霉烯酶是其对亚胺培南耐药的主要机制之一.     

分离自老年病房的鲍曼不动杆菌耐药机制初步研究*

目的:检测老年住院患者分离的鲍曼不动杆菌的主要耐药基因,并研究不同耐药基因型与耐药表型之间的对应关系。方法:用PCR方法检测分离自老年住院患者的不同标本来源的170例非重复鲍曼不动杆菌的耐药基因。检测的耐药基因包括D类碳青霉烯酶:bla_(OXA-51),bla_(OXA-23),bla_(OXA-24),bla_(OXA-58),B类金属碳青霉烯酶:bla_(VIM),bla_(IMP),bla_(SIM),bla_(GIM),bla_(DIM),bla_(NDM-1),以及A类超广谱β-内酰胺酶:blaKPC,共计11种。根据检测结果对菌株进行基因分型,并研究不同基因型与CRAB和CSAB这两种耐药表型之间的对应关系。结果:170株鲍曼不动杆菌的固有基因bla_(OXA-51)均为阳性,此外,主要检出基因为bla_(OXA-23),共124株。另外检测出blaKPC12株,bla OXA-58 6株,bla_(NDM-1)3株,bla_(SIM)2株,bla_(OXA-24)、bla_(VIM)和bla_(DIM)各1株,IMP和GIM未检出。根据检出耐药基因的不同组合,分为bla OXA-51+bla_(OXA-23)阳性为基础的A型(124株)及bla_(OXA-23)阴性为基础的B型(bla_(OXA-51),39株)、C型(bla_(OXA-51)+bla_(OXA-58),6株)、D型(bla_(OXA-51)+bla_(OXA-24),1株)共计四类基因型。从耐药表型来看,128株碳青霉烯耐药菌中有122株bla_(OXA-23)为阳性,在CRAB中占95.3%(122/128),42株碳青霉烯敏感株中,有40株bla_(OXA-23)为阴性,在CSAB中占95.2%(40/42)。结论:老年病房流行的耐碳青霉烯鲍曼不动杆菌的耐药基因型以bla_(OXA-23)阳性为主。其与鲍曼不动杆菌CRAB耐药表型、bla_(OXA-23)阴性与CSAB耐药表型之间有良好的对应关系。     

耐碳青霉烯类鲍曼不动杆菌OXA基因检测及同源性分析

目的 了解台州地区碳青霉烯类耐药鲍曼不动杆菌的耐药性、碳青霉烯酶基因型以及同源性.方法 63株碳青霉烯类耐药鲍曼不动杆菌经VITEK2 Compact进行细菌鉴定及药敏分析,用K-B法复核药敏结果,采用多重PCR扩增分析碳青霉烯酶的基因型;采用脉冲场凝胶电泳(pulsed field gel electrophoresis,PFGE)分析其同源性.结果 63株菌株为多重耐药菌株,除多粘菌素、阿米卡星、头孢哌酮/舒巴坦外,对其他常用抗生素的耐药率均在70％以上.63株菌株检测出OXA-51基因60株(95.2％),OXA-23基因58株(92.1％),两个基因同时存在的有58株(92.1％).PFGE结果显示碳青霉烯类鲍曼不动杆菌主要分为5个克隆型,其中A、B两个为主型.结论 产OXA酶是台州地区耐碳青霉烯类鲍曼不动杆菌的主要耐药机制之一,其中OXA-23是主要的基因型.     

2007-2010四年间鲍曼不动杆菌耐药性变迁及对亚胺培南耐药的机制研究

目的研究2007-2010四年间中山大学附属第一医院临床分离的鲍曼不动杆菌的耐药性迁移情况和耐亚胺培南的鲍曼不动杆菌(IRAB)的耐药机制,为临床抗感染治疗提供依据。方法采用VITEK 2型全自动微生物检测系统对细菌进行鉴定及药敏分析;用PCR方法检测碳青霉烯酶基因blaOXA-51、blaOXA-23、blaOXA-24和blaOXA-58。结果 2007-2010四年间分离鲍曼不动杆菌811株,耐药率逐年上升,其对头孢哌酮/舒巴坦、美罗培南、头孢吡肟、亚胺培南和哌拉西林/他唑巴坦的耐药率上升明显,如对亚胺培南的耐药率自2007-2010年分别为13.1%、26.0%、44.3%和59.5%。811株鲍曼不动杆菌中IRAB有311株,IRAB对抗生素的耐药率明显升高,但四年间的耐药率变化并不明显。对IRAB敏感的抗生素以阿米卡星为首,其次为头孢哌酮/舒巴坦,但头孢哌酮/舒巴坦的敏感率逐年下降。从311株IRAB中随机抽取140株,检出blaOXA-51基因阳性125株(89.3%),blaOXA-23基因阳性29株(20.7%),blaOXA-24基因阳性3株(2.14%),blaOXA-58基因阳性22株(15.7%)。结论鲍曼不动杆菌的耐药性逐年升高,以阿米卡星与头孢哌酮/舒巴坦联合应用为有效的治疗方法,产碳青霉烯酶是IRAB的主要耐药机制。     

鲍曼不动杆菌耐药性监测与碳青霉烯酶基因型研究

目的:对鲍曼不动杆菌耐药性及碳青霉烯酶基因型进行研究,以指导临床合理应用抗生素。方法:收集青岛市海慈医疗集团2009年6月至2010年6月从临床分离的鲍曼不动杆菌60株,用琼脂稀释法测定最低抑菌浓度(M IC),改良Hodge试验检测碳青霉烯酶,用PCR法检测OXA-23,OXA-24,OXA-58基因,并对PCR产物进行测序。结果:①鲍曼不动杆菌检出率前两位是ICU病房和呼吸科病房,分别占32.3%和27.4%,多重耐药鲍曼不杆菌阳性率最高的是ICU,为70.6%(12/17),其次为呼吸科病房,为35.0%(7/20),哌拉西林、哌拉西林/他唑巴坦、头孢曲松、头孢他啶、头孢吡肟、亚胺培南、美罗培南、庆大霉索、阿米卡星、环丙沙星、左氧氟沙星、加替沙星、头孢哌酮/舒巴坦、氨曲南耐药率分别为92.3%、55.4%、88.6%、86.3%、80.3%、30.0%、35.0%、76.6%、79.6%、75.1%、87.1%、48.3%、42.0%和79.6%.②在21株耐碳青霉烯类鲍曼不动杆菌,有14株碳青霉烯酶表型阳性,检出率为66.7%,有18株PCR扩增出OXA-23基因,检出率85.7%,全部菌株blaOXA-24及blaOXA-58PCR扩增均为阴性,PCR产物测序表明与鲍曼不动杆菌(AY795964.1)blaOXA-23基因序列100%同源。结论:鲍曼不动杆菌多重耐药性严重;表型和基因型检测证实本院临床分离鲍曼不动杆菌对碳青霉烯类耐药机制主要是产OXA-23型酶。     

The role of bla(OXA-like carbapenemase) and their insertion sequences (ISS) in the induction of resistance against carbapenem antibiotics among Acinetobacter baumannii isolates in Tehran hospitals

This study aimed to evaluate the occurrence and dissemination of bla(OXA-like) carbapenemase genes and their insertion sequences among Acinetobacter baumannii isolates, taken from different hospitals in Tehran city and also their roles in the induction of resistance to carbapenem drugs. A total number of 100 non duplicate Acinetobacter baumannii with different origins, were isolated from patients with proved nosocomial infections at eight university hospital in Tehran city. Antimicrobial susceptibility of these strains was done by E-test against 7 antimicrobial agents according to CLSI guideline. PCR of bla(OXA-51-like), bla(OXA-23-like), bla(OXA-24-like), bla(OXA-58-like), IS(ABA-1), IS(1133) was carried out by specialized primers and then these strains were typed by REP-fingerprinting. Colistin, imipenem and meropenem were the most sensitive antibiotics against Acinetobacter baumannii isolates with 96%, 51% and 51% sensitivity respectively. All the isolates had a bla(OXA-51-like) intrinsic to these species. The rates of bla(OXA-23), 23 and 58-like were 38%, 32% and 1% respectively. Coexistence of bla(OXA-51/23/24-like) was observed among 16% of these isolates. All bla(OXA-23-like) carbapenemase genes had only one IS(ABA1). REP fingerprinting showed 5 genotypes among carbapenem resistant isolates, 16 of them being genotype A. This study emphasized on the major role of bla(OXA-like) carbapenemase, particularly bla(OXA-23-like) carbapenemase and their IS(ABA1), in the dissemination of carbapenem resistant Acinetobacter baumannii. This study confirmed a presumptive role of IS element neighboring the carbapenemase gene in the elevation of resistance to carbapenem drug among Acinetobacter baumannii isolates for the first time in Iran.     

鲍曼不动杆菌对碳青霉烯类抗生素的耐药性及其基因的分析

目的研究23株鲍曼不动杆菌对碳青霉烯类抗生素的耐药情况及对耐药基因分析,为临床用药提供依据。方法用珠海迪尔DL-96鉴定系统进行细菌鉴定及K-B法进行药敏试验,用碳青霉烯酶4种基因的特异性引物对其进行聚合酶链反应(PCR)扩增和基因型分析,并通过网上GenBank进行比对以确定编码酶基因的类型。结果 23株鲍曼不动杆菌对哌拉西林/他唑巴坦、左旋氧氟沙星、丁胺卡那霉素、多黏菌素B的耐药率分别为80%、45%、30%、10%,对其他抗生素的耐药率均在90%以上。携带D类碳青霉烯酶OXA-23基因有18株(78%),携带OXA-51基因有15株(65%),OXA-24、OXA-58基因引物PCR扩增为阴性,随机各抽取3株OXA-23基因阳性株进行测序后通过在网上GenBank比对与OXA-23标准株99%同源,OXA-51基因阳性株与OXA-51标准株98%同源。结论耐碳青霉烯类抗生素的鲍曼不动杆菌对多黏菌素的耐药率最低,其次是丁胺卡那霉素,其中以携带OXA-23型碳青霉烯酶基因为主,应引起临床高度关注,防止在院内广泛传播。     

Gram-negative bacteriae with resistance to carbapenems

Clinically-significant Gram-negative species remain mostly Enterobacteriaceae, Pseudomonas aeruginosa and Acinetobacter baumannii. Carbapenem molecules are often the last resort for treating infections due to multidrug resistant isolates. In Enterobacteriaceae, resistance to carbapenems may result from combined mechanisms of resistance associating b-lactamases with weak (if any) intrinsic carbapenemase activity and decreased outer membrane permeability, or from true carbapenemases. KPC-type enzymes (partially inhibited by clavulanic acid) have been identified mostly in Klebsiella pneumoniae, first in bacteria identified in the USA and then worldwide, and in many enterobacterial species. Carbapenem-hydrolyzing b-lactamases (CHBL) could be also metallo-b-lactamases (VIM, IMP, NDM-1, etc.) mostly in hospital-acquired K. pneumoniae. One of the latest reported CHBL in Enterobacteriaceae is OXA-48, identified mostly in Mediterranean countries. All these carbapenemase producers are difficult to detect in a clinical laboratory and may be the source of multidrug resistance leading to a therapeutic dead end. Whereas the main mechanism of resistance to imipenem in P. aeruginosa remains due to a modification of the outer membrane protein OprD, the landscape of CHBL in P. aeruginosa expanding worldwide is made of KPC, GES-related enzymes and metallo-b-lactamases (IMP, VIM, etc.). These enzymes are involved in multidrug resistance strains as a source of nosocomial outbreaks. In Acinetobacter baumannii, KPC and metallo-b-lactamases have been identified. However, the most frequent CHBL are oxacillinases (OXA-23, OXA-40, OXA-58, OXA-143) which are specific to that species. Novel carbapenemases are continuously being identified worldwide with exchange of the resistance genes between Enterobacteriaceae, P. aeruginosa and A. baumannii.     

Prevalence of OXA-type carbapenemase genes and genetic heterogeneity in clinical isolates of Acinetobacter spp. from Mangalore, India

The prevalence of OXA-type carbapenemase genes, ISAba1 insertion sequence, carbapenem resistance, biofilm forming ability and genetic heterogeneity in clinical isolates of Acinetobacter spp. from hospitals in Mangalore, South India was studied. Based on the presence of the bla(OXA-51) -like gene, the 62 isolates of Acinetobacter spp. were identified as 48 A. baumannii and 14 other Acinetobacter spp. The prevalence of bla(OXA-23) -like, bla(OXA-24) -like and bla(OXA-58) -like genes in A. baumannii was 47.9%, 22.9% and 4.2%, while in other Acinetobacter spp. it was 28.5%, 64.3% and 35.7% respectively. Several A. baumannii isolates (16/48) harbored the insertion sequence ISAba1 in the upstream region of the bla(OXA-23) -like gene. Resistance to meropenem was seen in 39.6% and 14.2% of A. baumannii and other Acinetobacter spp. isolates, respectively. The ability to form biofilm was observed to be higher among A. baumannii in comparison to other Acinetobacter spp. The present study shows that bla(OXA-23) -like genes are more common in A. baumannii,whereas bla(OXA-24) -like genes are common to other Acinetobacter spp. The study revealed genetic heterogeneity among the isolates, indicating multiple sources in the hospitals.     

鲍曼不动杆菌对碳青霉烯类抗生素的耐药性分析

目的了解鲍曼不动杆菌的耐药情况,并检测耐碳青霉烯类鲍曼不动杆菌的耐药基因,为指导临床合理用药、控制院内感染提供依据。方法利用K-B法检测45株鲍曼不动杆菌临床分离株的耐药情况,通过改良Hodge试验、Carba NP试验和EDTA协同试验对多重耐药鲍曼不动杆菌的碳青霉烯酶进行表型检测,并采用PCR技术检测鲍曼不动杆菌携带OXA-23和NDM-1型耐药基因的情况。结果 45株鲍曼不动杆菌临床分离株中共筛出42株多重耐药菌株;利用改良Hodge试验和Carba NP试验检出36株碳青霉烯酶阳性菌株;采用PCR扩增出OXA-23,未扩增出NDM-1。结论鲍曼不动杆菌耐药情况严重,且耐药基因OXA-23携带率高,治疗时应根据药敏试验结果合理用药。     

First detection of OXA-24 carbapenemase-producing Acinetobacter baumannii isolates in Bulgaria

This report describes the first identification of OXA-24 carbapenemase-producing Acinetobacter baumannii isolates from Bulgaria. According to national surveillance data A. baumannii along with Pseudomonas aeruginosa are the most troublesome microorganisms in hospital environment with high rates of acquired carbapenem resistance. In the present study real-time multiplex PCR was performed to identify the most common carbapenemase genes in 15 non-duplicate carbapenem-resistant A. baumannii isolates collected in 2012. The results showed lack of KPC, GES, VIM, IMP-type enzymes. Four A. baumannii isolates tested positive by PCR for the acquired OXA-24 together with the intrinsic OXA-51 carbapenemase. OXA-24 and OXA-23 were determined as co-existent in one isolate. Two isolates were identified with OXA-23 in addition to the OXA-51 carbapenemase.     

Distribution of blaOXA genes among carbapenem-resistant Acinetobacter baumannii nosocomial strains in Poland

Acinetobacter baumannii is an important nosocomial pathogen occurring particularly in intensive care (ICU) as well as burn therapy units (BTU). A. baumannii strains have emerged as resistant to almost all antimicrobial agents, including carbapenems. b-lactamase-mediated resistance is the most common mechanism for carbapenem resistance in this species. Carbapenem-hydrolysing class D b-lactamases - OXA are widespread among A. baumannii strains. It is suggested that ISAba1 plays an important role in drug resistance. The aims of the study were detection of OXA encoding genes and presence of ISAba1. The study included the total of 104 isolates of carbapenem-resistant A. baumannii, obtained from patients hospitalized in ICU and BTU of Specialized Hospital in Krakow. Multiplex PCR was applied for detection of selected OXA carbapenemases encoding genes. PCR analysis showed the presence of bla OXA-51-like gene and ISAba1 in all isolates. 46 strains carried bla OXA-51-like and bla OXA-23-like genes while 48 bla OXA-51-like and bla OXA-40-like genes. 3 isolates carried: bla OXA-51-like , bla OXA-23-like and bla OXA-40-like genes. 7 strains encoded an OXA-51-like carbapenemase but were negative for enzymes belonging to the other families tested. Comparative analysis of ICU and BTU isolates revealed the dominance of: bla OXA-51-like and bla OXA-40-like among ICU while bla OXA-51-like and bla OXA-23-like in BTU.     

Outbreaks of imipenem-resistant Acinetobacter baumannii producing carbapenemases in Korea

Among 53 Acinetobacter baumannii isolates collected in 2004, nine imipenem-resistant isolates were obtained from clinical specimens taken from patients hospitalized in Busan, Korea. Nine carbapenemase-producing isolates were further investigated in order to determine the mechanisms underlying resistance. These isolates were then analyzed via antibiotic susceptibility testing, microbiological tests of carbapenemase activity, pI determination, transconjugation test, enterobacterial repetitive consensus (ERIC)-PCR, and DNA sequencing. One outbreak involved seven cases of infection by A. baumannii producing OXA-23 beta-lactamase, and was found to have been caused by a single ERIC-PCR clone. During the study period, the other outbreak involved two cases of infection by A. baumannii producing IMP-1 beta-lactamase. The two clones, one from each of the outbreaks, were characterized via a modified cloverleaf synergy test and an EDTA-disk synergy test. The isoelectric focusing of the crude bacterial extracts detected nitrocefin-positive bands with pI values of 6.65 (OXA-23) and 9.0 (IMP-1). The PCR amplification and characterization of the amplicons via direct sequencing showed that the clonal isolates harbored blaIMP-1 or blaOXA-23 determinants. The two clones were characterized by a multidrug resistance phenotype that remained unaltered throughout the outbreak. This resistance encompassed penicillins, extended-spectrum cephalosporins, carbapenems, monobactams, and aminoglycosides. These results appear to show that the imipenem resistance observed among nine Korean A. baumannii isolates could be attributed to the spread of an IMP-1- or OXA-23-producing clone. Our microbiological test of carbapenemase activity is a simple method for the screening of clinical isolates producing class D carbapenemase and/or class B metallo-beta-lactamase, in order both to determine their clinical impact and to prevent further spread.