血液透析患者血流感染CRKP耐药性及耐药基因型

Drug resistance and drug resistance genes in CRKP strains isolated from hemodialysis patients with bloodstream infection

目的 分析血液透析患者血流感染碳青霉烯耐药肺炎克雷伯菌(CRKP)耐药情况及耐药基因型。方法 收集2017年11月-2020年5月于湖州市中心医院血液净化中心治疗的血液透析患者血液标本分离的200株肺炎克雷伯菌,对分离的CRKP菌株进行药敏试验,采用聚合酶链式反应(PCR)检测耐药基因、血清荚膜分型以及毒力基因,并采用多位点序列分型(MLST)分析CRKP分型。结果 200株血流感染肺炎克雷伯菌中CRKP菌株为53株(26.50%),53株CRKP对几乎所有碳青霉烯类和其他β-内酰胺类抗菌药物耐药,对氨基糖苷类抗菌药物耐药率>45.00%;53株CRKP共检出48株携带KPC-2、NDM-1、CTM-M9基因菌株,未检出携带碳青霉烯酶基因菌株5株;53株CRKP仅检测到4株K1型菌株,共有58.49%(31/53)CRKP携带毒力基因,rmpA2、iutA为两种主要的毒力基因;53株CRKP中50株为ST11型,ST550、ST1517、ST2230各1株。结论 血液透析患者血流感染CRKP耐药现象较为严峻,其主要耐药机制是携带耐药基因KPC-2,主要毒力基因为rmpA2、iutA,以ST11型为流行序列型。

OBJECTIVE To analyze the drug resistance and drug resistance genotypes of carbapenem-resistant Klebsiella pneumoniae(CRKP) strains isolated from hemodialysis patients with bloodstream infection. METHODS Totally 200 strains of K.pneumoniae were isolated from blood specimens of the hemodialysis patients who were treated in blood purification center of Huzhou Central Hospital from Nov 2017 to May 2020, the drug susceptibility testing was carried out for the isolated CRKP strains, the drug resistance genes, serum capsular types and virulence genes were detected by means of polymerase chain reaction(PCR), and the types of CRKP strains were observed by using multilocus sequence typing(MLST). RESULTS Among the 200 strains of K.pneumoniae isolated from the patients with bloodstream infection, 53(26.50%) were CRKP. The 53 strains of CRKP were resistant to almost all of the carbapenems antibiotics and other β-lactams antibiotics, the drug resistance rate to aminoglycosides was more than 45.00%. 48 of 53 CRKP strains were detected to carry with KPC-2, NDM-1 and CTM-M9 genes, 5 strains did not carry with carbapenemase genes, only 4 of 53 CRKP strains were K1 type strains;totally 58.49%(31/53) of the CRKP strains carried with virulence genes, rmpA2 and iutA were the two major virulence genes. Among the 53 strains of CRKP, there were 50 strains of ST11, 1 strain of ST550, 1 strain of ST1517 and 1 strain ST2230. CONCLUSION The CRKP strains isolated from the hemodialysis patients with bloodstream infection are highly drug-resistant, its carrying with drug resistance gene KPC-2 is the major resistance mechanism, rmpA2 and iutA are the major virulence genes, and the ST11 type is the prevalent sequence type.