多重耐药肺炎克雷伯菌获得性耐药相关基因和可移动遗传元件检测与指标聚类分析

目的 探讨一组多重耐药肺炎克雷伯菌(MDR-KPN)中获得性耐药相关基因和可移动遗传元件遗传标记的存在状况以及二者的相关性.方法 收集2008年8月至2010年5月浙江省杭州市和湖州市6所医院共47株MDR-KPN,采用聚合酶链反应(PCR)的方法分析74种获得性耐药基因和24种可移动遗传元件遗传标记,并用指标聚类分析(SPSS法)分析获得性耐药相关基因和可移动遗传元件遗传标记的相关性.结果 47株MDR-KPN共检出5种β-内酰胺类获得性耐药基因、6种氨基糖苷类获得性耐药基因、3种喹诺酮类获得性耐药基因、6种其他获得性耐药基因、1种整合子遗传标记、2种转座子遗传标记、4种插入序列遗传标记、2种接合性质粒遗传标记和1种噬菌体原标记；指标聚类分析(SPSS法)将上述阳性检出基因分成A、B两大簇.结论 指标聚类分析提示获得性耐药相关基因和可移动遗传元件密切相关；由Ⅰ类整合子( intI1)、插入序列(IS26、ISEcp1、ISKpn6)、耐药质粒(trbC)介导的TEM-1和KPC是本组菌株的特征.在肺炎克雷伯菌中做指标聚类分析为国内首次报道.

The index cluster analysis based on detection of acquired resistance genes and mobile genetic elements of multidrug-resistance of Klebsiella pneumonia

Objective To investigate the distribution of acquired resistance genes, genetic markers of mobile genetic elements and their relationship in muhidrug-resistant Klebsiella pneumonia （MDR-KPN）. Methods 47 strains of MDR-KPN were collected from 6 hospitals in Hangzhou and Huzhou from August 2008 to May 2010, and 74 kinds of acquired resistance genes and 24 sorts of genetic markers of mobile genetic elements were detected by PCR. Index cluster analysis was performed to investigate their correlation. Results In the 47 MDR-KPN strains, 5 acquired beta-lactam-resistant genes, 6 acquired aminoglycoside-resistant genes, 3 acquired quinolone-resistant genes, and 6 other acquired resistant genes, as well as 2 genetic markers of conjugal plasmids, 2 of transposons, 4 of insertion sequences, 1 of integron, and 1 of prophages were detected. The above positive genes were classified into two clusters of A and B by index cluster analysis. Conclusion Index cluster analysis showed a close correlation between acquired resistance genes and mobile genetic elements. The characteristics of this group of strains are acquired resistance genes （TEM-1 and KPC） induced by mobile genetic elements （Class I integrons, insertion sequences：IS26, ISEcpl, ISKpn6, resistance plasmid trbC）. And this is the first report that Klebsiella pneumonia was analyzed by index cluster analysis.