耐碳青霉烯铜绿假单胞菌耐药机制和传播机制研究

目的阐明南方医科大学南方医院耐碳青霉烯铜绿假单胞菌的耐药机制和传播机制。方法采用聚合酶链反应(PCR)-限制性核酸片段长度多态性分析分型和测序技术对临床分离的59株耐碳青霉烯铜绿假单胞菌进行整合子Ⅰ、插入序列共同区(ISCR1)和常见碳青霉烯酶基因研究,采用肠杆菌科间重复一致性序列(ERIC)-PCR技术研究传播机制。结果 59株菌株中20株(34%)整合子Ⅰ阳性,17株(29%)整合子Ⅰ可变区阳性;9株(15%)ISCR1阳性,5株(8%)ISCR1可变区阳性且均携带qnrA1和ampR耐药基因盒。1株检出复杂性整合子Ⅰ,3株检出VIM-2基因,2株检出IMP-1基因。ERIC-PCR聚类分析在80%相似水平上聚为52个类群。结论整合子Ⅰ、ISCR1和碳青霉烯酶在铜绿假单胞菌介导多重耐药方面有重要作用,ERIC-PCR是进行铜绿假单胞菌同源性分析的有效方法。

Study on mechanism of drug resistance and transmission in carbapenems-resistant pseudomon asaeruginosa isolates ~

Objective To investigate the mechanism of drug resistance and transmission in carbapenems-resist- ant pseudomon asaeruginosa isolates. Methods Polymerase chain reaction （PCR）, restriction fragment length poly- morphism-PCR （RFLP-PCR） and sequencing were used to detect class I integron, ISCR1, and carbapenemases genes in 59 carbapenems-resistant pseudomon asaeruginosa isolates. ERIC-PCR was determined for genotype of isolates. Results Among 59 bacterial isolates, 20 class I integrase, 17 class I integrons,5 ISCR1 carrying qnrA1 and ampR resistance genes were detected and 3 harboured VIM-2,2 harboured IMP-1 genes, but none other earbapenemases genes was found. All bacterial isolates contained 52 genotypes at similarity level of 80%. Conclusion Class I inte- gron,ISCR1 and carbapenemases might play an important role in mediating multidrug resistance in pseudomon asaeruginosa. ERIC-PCR could be a convenient and effective method for genotyping clinical pseudomon asaeruginosa isolates.