重症监护病房产ESBLs菌的基因分型

目的了解深圳市人民医院重症监护病房分离菌超广谱β-内酰胺酶（ESBLs）的检出率及其基因型分布情况。方法收集来自重症监护病房大肠埃希菌和肺炎克雷伯菌分离株48株,采用CLSI推荐的表型确证方法筛选出ESBLs株,并利用PCR及DNA测序法分析产酶菌株的ESBL基因型。结果（1）48分离株菌中共检出产ESBLs菌24株,阳性率为50.0%。（2）产酶菌中93.8%（15/16）的大肠埃希菌和87.5%（7/8）的肺炎克雷伯菌分别检出CTX-M基因;其中72.7%（16/22）为CTX-M-14。6株肺炎克雷伯菌检出SHV基因,其中3株为SHV-11型,另3株为SHV-12型,6株含SHV基因的肺炎克雷伯菌中5株合并CTX-M基因。而所有大肠埃希菌株均未检出SHV基因。所有产酶菌中,分别有10株大肠埃希菌和2株肺炎克雷伯菌检出TEM-1基因,其中1株大肠埃希菌只检出TEM-1基因,未检出SHV型或CTX-M型基因。结论重症监护病房分离菌ESBLs检出率高,以CTX-M-14为主要基因型。

The genotypes of ESBL-producing isolates in intensive care unit

Objective To investigate the detection rate and genotypic character of extended spectrum beta-lacta-mases (ESBLs) in isolates from intensive care unit(ICU) in Shenzhen People's Hospital. Method Phenotyic confirmatory test which recommended by CLSI was performed to detect ESBLs in 48 Escherichia coli and Klebsiella pneumoniae isolates, and the ESBL-genotypes were determined by using PCR and DNA sequencing. Result (1)24 in 48 isolates were detected producing ESBLs, with the detection rate of 50%. (2) In all ESBL-producing isolates,93.8% of Escherichia coli and 87. 5% of Klebsiella pneumoniae were found harbouring CTX-M gene, 72. 7% of them were CTX-M-14. Six Klebsiella pneu-moniae isolates were found carrying SHV gene, three of them were SHV-11 and the others were SHV-12. And five in these six SHV-type Klebsiella pneumoniae isolates were harbouring CTX-M gene. SHV gene was not detected in Escherichia coli I-solates. In all the ESBL-producing isolates, 10 strains of Escherichia coli and 2 of Klebsiella pneumoniae were found carrying TEM-1 gene, and one of them carrying only TEM-1 but not the others . Conclusion The detection rate of ESBL is high in isolates from ICU in this hospital,the major genotype of the ESBLs-producing isolates is CTX-M-14.