产超广谱β-内酰胺酶大肠埃希菌的检测及耐药性分析

Detection of extended-spectrum β-lactamases-producing Escherichia coli and its antibiotic resistance analysis

目的研究产超广谱β-内酰胺酶(ESBLs)大肠埃希菌的发生及耐药性,为临床抗感染治疗合理使用抗生素提供指导。方法用美国临床实验室标准化研究所推荐的初筛试验和表型确证试验检测ESBLs产生株,使用最低抑菌浓度法和K-B法检测临床各类标本中分离的216株大肠埃希菌对22种抗生素的耐药情况。结果216株大肠埃希菌ESBLs检出率为59.3%,产ESBLs大肠埃希菌对大多数β-内酰胺类药物明显耐药,并对氨基糖苷类、氟喹诺酮类多数耐药,耐药率明显高于非产ESBLs大肠埃希菌,但对亚胺培南100%敏感。结论产ESBLs大肠埃希菌大多为多重耐药菌,其耐药性明显高于非产ESBLs大肠埃希菌,临床微生物实验室应加强对产ESBLs菌株的监测。

Objective To study the incidence and antibiotic resistance of ESBLs-producing Escheriehia coli （E. coli）, in order to further guide rational use of antibiotics in clinical therapy. Methods ESBLs-producing strains were screened by initial screening test and confirmed by the phenotypic confirmatory test recommended by Clinical and Laboratory Standards Institute （CLSI）. The antibiotic resistance of 216 strains of E. coli, which were isolated from clinical specimens, against 22 antibiotics was determined by MIC assay and Kirby-Bauer disk diffusion method. Results The positive rate of ESBLs-producing E. coil strains was 59. 3%. The resistance of ESBLs producing strains to most β-1actams, fluoroquinolones and aminoglycosides, while much higher than those of non-ESBLs produ- cing strains. No strains were found to be resistant to imipenem. Conclusion ESBLs-producing strains are mostly multi-drug resistant, which drug resistance is much higher than those of non-ESBLs producing strains. It is important to monitor the statue of ESBLs-producing bacteria in clinical microbiological laboratory.