【摘要】 目的了解大肠埃希菌产β-内酰胺酶(BLA)的类型及其耐药特征。方法采用生物梅里埃ATB系统G-5药敏条做药敏试验。用NCCLs确证试验检测超广谱β-内酰胺酶(ESBLs),根据表型检测AmpCBLA、对β-内酰胺酶抑制剂敏感性下降的BLA和水解碳青霉烯类的BLA。结果162株大肠埃希菌产ESBLs74株(45.7%);表型鉴别产AmpCBLA9株(5.6%)、对β-内酰胺酶抑制剂敏感性下降的BLA2株(1.2%)、未检到水解碳青霉烯类的BLA。药敏结果显示产ESBLs菌对20种抗菌药物的耐药率均显著高于非产酶菌株(亚胺培南、美洛培南除外)。碳青霉烯类、阿米卡星、头孢西丁对产ESBLs菌有较高活性。头孢他定、头孢噻肟的耐药率差异显著分别为25.0%和91.7%。结论大肠埃希菌以产ESBLs为主,筛选时以头孢噻肟为检测底物优于头孢他定。产ESBLs菌耐药率明显高于非产酶株,碳青霉烯类是目前少数对ESBLs高度稳定的抗生素之一。更多还原

【Abstract】 Objective To study β-lactamases(BLA) types producting from Escherichia coli and drug-resistant characteristics. Methods Sensitivity of drugs was detected by ATB antibiogram method of bioMerieux. Extended-spectrum β-lactamases(ESBLs) were determined using confirmatory test recommended by NCCLS. AmpC BLA (ABLs), sensibility to BLA-inhibitor lessening BLA, and hydrolyzing carbapenem BLA were detected according to phenotype observation. Results Among 162 isolates of E. Coli, 74 strains produced ESBLs(45.7%); 9 strains produced ABLs(5.6%); 2 strains produced sensibility to BLA-inhibitor lessening BLA (1.2%); hydrolyzing carbapenem BLA was not detected out. The resistance rates of ESBLs-producing strains to 20 antibacterial agents were significantly higher than those of non-ESBL-producing strains(except for imipenem, meropenem). Carbapenems Amikacin and Cefoxitin were susceptible to ESBLs-producing E.coli; and the rate of the drug resistance to Cefotaxime and Ceftazidime attained 25.0% and 91.7%. Conclusions ESBLs is one of major BLA for E.coli. The sensitivity substrate of ESBLs, cefotaxime was higher than that of ceftazidime. The resistance rates of ESBLs-producing strains were significantly higher than those of non-ESBL-producing strains. Carbapenems is one of the susceptible antibiotics to ESBLs-producing strains.更多还原