长沙某医院产质粒AmpC酶型肺炎克雷伯菌的多重PCR检测与分析

为了了解湖南长沙某医院临床分离的肺炎克雷伯菌中质粒介导AmpC β-内酰胺酶的产生情况及其基因型,收集了该医院2008年3月至2010年10月临床分离的多重耐药肺炎克雷伯菌104株,用头孢西丁纸片扩散法对这些菌株进行表型初筛,用多重PCR确定ampC耐药基因型;结果发现其中有19株对头孢西丁纸片不敏感,疑为产AmpC酶菌株;再经多重PCR扩增,有12株菌分别在约400 bp（11株）和约350 bp（1株）出现了阳性条带,特异性PCR证明此12株菌分别携带了DHA型（11株）和ACC型（1株）ampC耐药基因;产质粒介导AmpC酶肺炎克雷伯菌的分离率为11.5%（12/104）。该医院产质粒介导AmpC酶肺炎克雷伯菌的分离率较高,应对其检测与监测给予足够重视,以指导临床合理选用抗菌药物。

Analysis and Detection of Plasmid-mediated AmpC β-lactamase Genes in Klebsiella pneumoniae of One Hospital in Changsha by Using Multiplex PCR

To investigate the prevalence and genotype of the plasmid-mediated AmpC β-lactamases of Klebsiella pneumoniae in clinical isolates from one hospital of Changsha,a total of 104 non-duplicate clinical isolates of Klebsiella pneumoniae,which were saved mindedly from March 2008 to October 2010 in this hospital,were selected by cefoxitin disk diffusion test firstly.Then multiple PCR method was employed to test ampC resistance genotypes in AmpC enzyme phenotype-positive Klebsiella pneumoniae strains.Among the 104 Klebsiella pneumoniae clinical isolates,19 strains were not sensitive to cefoxitin disk.12 strains of these 19 non-sensitive clinical isolates were presented positive at the 400 bp bands(11 strains) and 350 bp band(1 strain) separately by multiple PCR,and the specific PCR determined that these 12 strains carried DHA type(11 strains) and ACC type(1 strain) ampC resistance gene seperately.The separation rate of producing plasmid-mediated AmpC enzyme of Klebsiella pneumoniae was 11.5%(12/104).The separation rate of producing plasmid-mediated AmpC enzyme of clinical isolates of Klebsiella pneumoniae strains in this hospital is high,and much attention should be paid to their detections and surveillance.