【摘要】 目的研究深圳市人民医院2002年1月-2003年12月临床下呼吸道分离的产ESBLs大肠埃希菌和肺炎克雷伯菌的耐药性、ESBLs基因型以及基因型和耐药表型的相关性。方法共收集临床下呼吸道分离产ESBLs大肠埃希菌和肺炎克雷伯菌61株,采用酶抑制剂增强法作表型确证试验,琼脂稀释法作药敏试验,应用PCR、序列分析,确定ESBLs基因型。结果61株产ESBLs大肠埃希菌和肺炎克雷伯菌对亚胺培南的敏感率是100％,MIC90 0．5 mg／L,两种细菌表现出不尽相同的耐药表型。共检出10种β内酰胺酶基因型,CTX—M型、SHV型和TEM型的检出率依次为83．6％、44．3％和37．7％,其中以CTX-M-14最多,共38株;SHV型仅见于肺炎克雷伯菌,SHV-12最常见,有20株;TEM型均为TEM-1。结论本院临床下呼吸道产ESBLs大肠埃希菌和肺炎克雷伯菌耐药情况严重,为多重耐药菌。ESBLs有7种基因型,CTX—M型是主要的基因型,其次是SHV型;两种菌中各基因型的分布不同,其耐药表型也不同。更多还原

【Abstract】 Objective To investigate the resistance and prevalence of extended-spectrumβ-lactamases (ESBLs) genotypes in Escherichia coli and Klebsiella pneumoniae which were isolated from lower respiratory tract between Jan 2002 and Dec 2003 in Shenzhen People’s Hospital. Methods Sixty-one strains were confirmed as ESBLs-positive with inhibitor-potentiated test. The MICs were determined by agar dilution. ESBL genotypes were analyzed by PCR and nucleotide sequencing analysis. Results The susceptibility rate of ESBLs- producing strains were 100% to imipenem, MIC90 0. 5 mg/L. A total of 10 genotypes ofβ-lactamases were identified in the 61 ESBLs- producing strains. CTX-M type was identified in 83. 6% of the strains, including CTX-M-14 in 38 strains. SHV type was identified in 44. 3% of the strains, including SHV-12 in 20 strains. SHV genotype was identified only in K. pneumoniae. TEM type was identified in 37. 7% of the isolates. All of them were TEM-1. Conclusions ESBLs-producing E. coli and K. pneumoniae strains isolated from lower respiratory tract are highly resistant. Most strains are resistant to multiple drugs. CTX-M-type is the predominant ESBL genotypes in E. coli and K. pneumoniae, followed by SHV-type. Moreover, the distribution of ESBL genotypes is different in E. coli and K. pneumoniae, which may contribute to the different resistance patterns.更多还原