天津地区产质粒Amp C酶和超广谱β-内酰胺酶大肠杆菌的耐药酶基因研究  

A study on plasmid-mediatied Amp C beta-lactamases and extended-spectrum β-lactamases of Escherichia coli in Tianjin

作　　者：刘敏[1] 郝邯生[1] 

机构地区：[1]武警医学院附属医院传染科,天津300162

出　　处：《武警医学》2008年第9期821-824,共4页Medical Journal of the Chinese People's Armed Police Force

摘　　要：目的了解天津地区产质粒AmpC酶和超广谱β-内酰胺酶（ESBLs）的大肠杆菌的流行情况及其耐药酶的基因型分布。方法收集2006年3-12月天津地区两家三级甲等医院临床分离的对三代头孢菌素耐药的大肠杆菌，采用三维试验法检测Amp C酶；纸片确认试验法检测超广谱酶；质粒接合试验定位耐药酶基因；PCR通用引物扩增Amp C酶与超广谱酶基因以确定其基因型。结果在86株受试菌中，表型确认法的AmpC酶检出率为13．95％；超广谱酶检出率为63．95％；同时阳性者为8．14％。8株Amp C酶基因扩增阳性菌中有6株扩增出CTT型片段，3株扩增出DHA型片段。3株Amp C酶基因扩增阳性同时合并超广谱酶阳性菌中：1株扩增出TEM型和CTX-M-3型片段，1株扩增出TEM型和CTX-M-14型片段，1株同时扩增出TEM型、CTX-M-3和CTX-M-14型片段。结论天津地区存在同时产质粒Amp C酶和超广谱酶的大肠杆菌流行株，且某些菌株的耐药酶基因型组合在国内其他地区尚未见报道。Objective To investigate the prevalence and genotype of Eseherichia coli（ E. eoli） producing plasmid - mediated Amp C β- lactamases and extended- spectrum β- laetamases（ESBLs）.Methods Strains of third- generation cephalosporin resistant E. coli at two hospitals in Tianjin were collected from March to December 2006. Three - dimensional extract test and phenotypic confirmatory test were used for idenfificalion of Amp C β- lactamases and ESBLs separately. Locations of the β- laetamase genes were determined by plasmid conjugation test.Polymerase chain reaction（PCR） was used to identify the specific genotype of Amp C β- laetamases and ESBLs with universal primers. Results Among86 strains included in this study, the prevalence rates of Amp C β- lactamases and ESBL2 were 13.95% and 63.95%,respectively; the detection rate of double positive isolates was 8.14% .Eight strains of E. coli were positive for Amp C β- laetamases gene amplification（6 strains for CIT type;3 strains for DHA type）. Among the eight strains,three were combined with ESBIL2 positive;their genotypic combinations were TEM and CTX - M - 3（E.59） ; TEM and CTX - M - 14 （E112） ; TEM, CTX - M - 3 and CTX - M - 14 （E220） respectively. Ceedusions The clinical isolates of E. coli producing both plasmid- mediated Amp C β- lactamases and ESBLs were found in Tianjin.

关 键 词：大肠杆菌 AMP C酶 超广谱Β-内酰胺酶 

分 类 号：R978.11[医药卫生—药品] R915[医药卫生—药学]