铜绿假单胞菌DHA-1型AmpC酶的检测及耐药性分析  

Detection of DHA-1 Ampc enzymes in Pseudomonas aeruginosa and analysis of their drug resistance

作　　者：金保富[1] 林平[2] 陈佳玉[2] 

机构地区：[1]浙江省台州医院,临海317000 [2]浙江省台州学院医学院,椒江318000

出　　处：《中国抗生素杂志》2012年第7期510-513,共4页Chinese Journal of Antibiotics

基　　金：台州学院培育基金项目(No.2010PY40)

摘　　要：目的调查临床分离铜绿假单胞菌ESBLs、AmpC酶的产生、AmpC酶的基因型及对常用抗菌药物的耐药特征。方法采用VITEK-60型全自动细菌鉴定仪鉴定细菌;ESBLs检测及药敏试验按CLSI推荐的双纸片确证法和K-B纸片扩散法;AmpC酶检测采用头孢西丁纸片扩散法筛选疑产阳性菌株,再经三维试验确诊;PCR扩增DHA结构基因。结果铜绿假单胞菌产ESBLs和AmpC酶总检出率分别为40.8%和38.2%,其中,单产AmpC酶、单产ESBLs和同产AmpC酶+ESBLs检出率分别为19.7%、26.3%和14.5%;26株三维试验阳性菌株PCR扩增出23株DHA-1型酶基因;药敏试验显示:产酶株的耐药性明显高于非产酶株,耐药现象在同产AmpC酶和ESBLs菌株中更为严重,产酶株和非产酶株对亚胺培南均有较高的敏感性。结论临床分离的铜绿假单胞菌产ESBLs和AmpC酶菌株检出率较高;AmpC酶基因型以DHA-1型为主要流行株;产AmpC酶和ESBLs的菌株呈高度耐药。Objective To explore the production of ESBLs, AmpC enzyme and genotype of AmpC enzyme in clinically isolated Pseudomonas aeruginosa, and their resistance to common antibiotics. Methods Bacteria were identified with VITEK-60, ESBLs were detected and drug sensitive test was performed in accordance with the double disk confirmatory test and K-B disk diffusion recommended by the CLSI, AmpC enzymes were detected by screening suspected positive strains with cefoxitin disk diffusion method and confirming them by a three-dimensional test, and structural genes were amplified by using PCR. Results The detection rates of ESBLs- and AmpC enzyme-producing Pseudomonas aeruginosa were respectively 40.8% and 38.2%, among which 19.7% produced only AmpC enzymes, 26.3% produced only ESBLs and 14.5% produced both of them. The 26 positive isolates confirmed by the three- dimensional test were found to have 23 strains of DHA-1 gene by PRC amplification. Drug sensitive tests indicated that the resistance of enzyme-producing strains to drugs was significantly higher than that of non-enzyme-producing ones, especially so in those producing both ESBL and AmpC enzyme, and imipenem was more sensitive to both enzyme-producing and non-enzyme-producing strains. Conclusion ESBLs- and AmpC enzyme-producing strains from clinically isolated Pseudomonas aeruginosa have a higher detection rate. AmpC enzyme genotype is mainly of DHA-1 type. ESBLs and AmpC enzyme-producing strains have higher resistance to drugs.

关 键 词：铜绿假单胞菌 AMPC酶 DHA-1型 ESBLS 耐药性 

分 类 号：R378.991[医药卫生—病原生物学]