肺炎克雷伯菌产ESBLs基因型分析

目的 分析我院临床分离的肺炎克雷伯菌产ESBLS基因型，为指导临床合理用药提供依据。方法 用琼脂稀释法检测10种抗菌药物对已确定为产ESBLS肺炎克雷伯菌的MIC，分别用TEM、SHV、CTX-M、OXA通用引物进行PCR扩增、产物克隆测序分析。结果 83株产ESBLS肺炎克雷伯菌中，产TEM型75株，SHV型41株，CTX-M型25株，OXA型9株。其中，同时产3种酶有13株，占15．7％；同时产2种酶有59株，占71．1％；仅11株产单1种酶，占13．2％。而9株同时产TEM、SHV和CTX-M型，测序结果为CTX-M-3，TEM-1及多种SHV型（SHV-12、SHV-28）。药敏结果表明，同时产2或3种酶的菌株比产单1种酶的菌株耐药性更严重。结论 所分离产ESBLS肺炎克雷伯菌主要为TEM、SHV、CTX-M、OXA型，且同时存在产2～3种酶，应引起临床高度重视。

Genotype analysis of ESBLs-producing Klebsiella pneumoniae isolates

Objective To identify the genotypes of ESBLs-producing Klebsiella pneumoniae isolates from the First Affiliated Hospital,Shantou University Medical College.Methods The MICs of 10 antibiotics were determined by agar-dilution against the clinical isolates of ESBLs-producing K.pneumoniae.PCR were performed with specific primers for blaTEM,blaSHV, blaCTX-M and blaOXA respectively.PCR products were cloned and sequenced.Results The results of PCR showed that a- mong the 83 strains of ESBLs-producing K.pneumoniae,75 were positive for blaTEM,41 positive for blaSHV,25 poitive for blaCTX-M,9 positive for hlaOXA.Three genotypes were found in 13 strains(15.7%),2 genotypes in 59 strains (71.1%) and single genotype in only 11 strains(13.2%).The genes of CTX-M-3,TEM-1 and SHV were found co-existent in 9 strains. The strains carrying 2 or 3 ESBL genes were more resistant to antibiotics than those carrying only 1 ESBL gene.Conclusions The genotypes of ESBLs-producing Klebsiella pneumoniae in this hospital are blaTEM,blaSHV,blaCTX-M and blaOXA. Most strains carry 2 or 3 ESBL genes.