CAJ | 학술논문

目的研究中国部分地区临床分离亚胺培南耐药鲍曼不动杆菌的碳青霉烯酶基因型及16s rRNA甲基化酶基因.方法收集6省市25家医院2004年12月至2005年12月临床分离的342株亚胺培南耐药鲍曼不动杆菌;采用琼脂稀释法和E-test法测定菌株对14种抗菌药物的最低抑菌浓度(MIC);脉冲场凝胶电泳(PFGE)分析亚胺培南耐药菌株同源性;PCR及克隆测序分析碳青霉烯酶基因和16S rRNA甲基化酶基因型.结果 342株亚胺培南耐药鲍曼不动杆菌对氨苄西林/舒巴坦、头孢哌酮/舒巴坦两个含舒巴坦制剂耐药率分别为68.0%、54.2%,对多粘菌素E耐药率最低为10.8%,对米诺环素耐药率75.9%,对妥布霉素耐药率87.4%,对其他抗菌药物的耐药率均在90%以上;342株亚胺培南耐药鲍曼不动杆菌PFGE分型中303株菌株属于6个广泛流行的克隆株;342株亚胺培南耐药鲍曼不动杆菌中322株携带OXA-23基因,全部携带OXA-66基因,314株菌株OXA-23基因上游榆测到插入序列ISAbal,13株OXA-66基因上游检测到ISAbal;287株对阿米卡星、庆大霉素、妥布霉素、异帕米星、奈替米星全部耐药的菌株巾有221株携带armA型16S rRNA甲基化酶基冈.结论 OXA-23组D类β-内酰胺酶基因是最主要的碳青霉烯酶基因型,插入序列ISAbal在介导鲍曼不动杆菌对哑胺培南耐药中起重要作用;16S rRNA甲基化酶基因armA基因在中国哑胺培南耐药鲍曼不动杆菌中分布广泛;克隆播散是亚胺培南耐药鲍曼不动杆菌最主要的传播方式.
목적 연구중국부분지구림상분리아알배남내약포만불동간균적탄청매희매기인형급16s rRNA갑기화매기인.방법 수집6성시25가의원2004년12월지2005년12월림상분리적342주아알배남내약포만불동간균;채용경지희석법화E-test법측정균주대14충항균약물적최저억균농도(MIC);맥충장응효전영(PFGE)분석아알배남내약균주동원성;PCR급극륭측서분석탄청매희매기인화16S rRNA갑기화매기인형.결과 342주아알배남내약포만불동간균대안변서림/서파탄、두포고동/서파탄량개함서파탄제제내약솔분별위68.0%、54.2%,대다점균소E내약솔최저위10.8%,대미낙배소내약솔75.9%,대타포매소내약솔87.4%,대기타항균약물적내약솔균재90%이상;342주아알배남내약포만불동간균PFGE분형중303주균주속우6개엄범류행적극륭주;342주아알배남내약포만불동간균중322주휴대OXA-23기인,전부휴대OXA-66기인,314주균주OXA-23기인상유유측도삽입서렬ISAbal,13주OXA-66기인상유검측도ISAbal;287주대아미잡성、경대매소、타포매소、이파미성、내체미성전부내약적균주건유221주휴대armA형16S rRNA갑기화매기강.결론 OXA-23조D류β-내선알매기인시최주요적탄청매희매기인형,삽입서렬ISAbal재개도포만불동간균대아알배남내약중기중요작용;16S rRNA갑기화매기인armA기인재중국아알배남내약포만불동간균중분포엄범;극륭파산시아알배남내약포만불동간균최주요적전파방식.
Objective To investigate the prevalence of 16S rRNA methylases gene in imipenem-resistant Acinetobacter baumannii isolates from China. Methods A total of 342 imipenem-resistant A.baumannii isolates were collected between December 2004 and December 2005, from 25 hospitals of China. Agar dilution was used to determinate the minimal inhibitory concentration (MIC) of these isolates. The homology of these isolates was analyzed by pulse-field gel electrophoresis (PFGE). Several 16S rRNA methylase genes and carbapenemase genes were detected by PCR-based assays and PCR products were sequenced. Results The rates of resistance to ampicillin-sulbactam, cefoperazone-sulbactam, tobramycin, and minocycline were 68.0%, 54.2%, 87.4%, and 75.9%, respectively. The rate of resistance to polymyxin E was 10.8%, the lowest among the tested agents. The rates of resistance to all other tested antimicrobial agents were more than 90%. The A.baumannii isolates belonged to 29 distinct clones. Among them, 6 clones were dominant, consisting of 303 isolates in total. All isolates contained the blaOXA-51-1ike gene (blaOXA-66) and 322 isolates contained the blaOXA-23-1ike gene. PCR with the ISAbal-OXA-23-like primers generated a PCR product in 314 isolates, and PCR with the ISAbal-OXA-51-1ike primers generated a PCR product in 13 strains. 221 armA-positive isolates were identified. Conclusion Most of the imipenem-resistant A.baumannii contained blaOXA-23, with ISAbal upstream of the gene. 16S rRNA methylase gene armA was widely distributed in these isolates. The results suggested that the spread of clones played an important role in the outbreak of imipenem-resistant A. baumannii in China.