摘要
目的检测广州市第一人民医院20株耐亚胺培南鲍曼不动杆菌的耐药性,研究并分型其碳青霉烯酶基因。方法用法国生物梅里埃公司VITEK2全自动细菌鉴定仪进行菌株鉴定和药敏试验,用6种碳青霉烯酶特异性基因引物进行PCR扩增和基因型的测序分析,并通过网上GenBank进行比对以确定编码酶基因的类型。结果 20株鲍曼不动杆菌对哌拉西林-他唑巴坦、左氧氟沙星和阿米卡星的耐药率分别为85%、50%和25%。对其他所测抗菌药的耐药率均在90%以上。扩增结果显示17株(85%)细菌携带碳青霉烯酶OXA-23基因,16株(80%)携带OXA-51基因,1株(5%)携带OXA 58基因。OXA-24、VIM、IMP基因引物PCR扩增均为阴性,随机抽取OXA-23基因阳性株进行双向测序后在网上GenBank比对与OXA-23标准株99%同源,OXA-51基因阳性株与OXA-66标准株99%同源,OXA-58基因阳性株与OXA-58标准株99%同源。结论我院耐碳青霉烯类抗生素的鲍曼不动杆菌呈现出多重耐药现象,对阿米卡星的耐药率最低,OXA-23型碳青霉烯酶基因检出率最高,OXA-23/OXA-51类基因占60%,应引起临床高度重视,防止在医院内广泛传播。
Objective To analyze antibiotic resistant phenotype and carbapenemase genotype of 20 strains of imipenem-resistant A. baumannii isolated in patients of Guangzhou First People＇s Hospital. Methods Merieux VITEK2 was used for strain identi- fication and susceptibility testing. Six carbapenemase-specific gene primers were applied in polymerase chain reaction （PCR） to amplify the target genes for sequencing analysis. The DNA sequence was submitted for online GenBank alignment analysis. Results The percentage of strains resistant to piperacillin tazobactam, levofloxacin and amikacin in the 20 A. bauraannii isolates was 85%, 50% and 25%, respectively. More than 90% of these strains were resistant to other antibiotics tested. OXA-23 gene was identified in 17 strains （85%）, OXA-51 in 16 strains （80%）, and OXA 58 gene in 1 strain （50%）. OXA-24, VIM, or IMP gene was not identified by PCR amplification. OXA-23 gene positive strains were randomly selected for two-way sequencing analysis. The sequence of our OXA-23 gene showed 9990 homology with the reference strain. OXA-51 gene-positive strains showed 99% homology with OXA 66 reference strain. OXA-58 gene positive strains showed 99% homology with OXA-58 reference strain. Conclusions The carloapenem-resistant A. baumannii strains isolated in our hospital are resistant to multiple drugs. These strains showed relatively lower resistance to amikacin. OXA-23 type carbapenemase gene is highly prevalent. OXA-23/OXA-51 type genes were prevalent in 60% of the strains. Attention should be paid to such resist-ance and its spread in hospital.
出处
《中国感染与化疗杂志》
CAS
2011年第1期45-48,共4页
Chinese Journal of Infection and Chemotherapy
关键词
鲍曼不动杆菌
多重耐药
碳青霉烯酶
基因
耐药率
Acinetobacterbaumannii
multi-drug resistance
carbapenemase
gene
resistance rate
