汕头地区产CTX-M型ESBLs肺炎克雷伯菌分析

Analysis of the epidemiology of CTX-M extended-spectrum β-lactamase in clinical isolates of Klebsiella pneumoniae in Shantou

目的了解汕头地区产CTX-M型ESBLs肺炎克雷伯菌的情况。方法用通用引物blaCTX-M对已确定为产ESBLs的肺炎克雷伯菌进行PCR扩增、脉冲场凝胶电泳(PFGE)分析,检测其对常见抗菌药物的耐药性。结果本地区CTX-M型ESBLs肺炎克雷伯菌检出率为30.1%(25/83),标本来源主要为痰液(24株);分布的临床科室为新生儿科、呼吸内科、神经外科、神经内科、儿科、外科ICU、心血管内科及普外科。与其它基因型同时存在较普遍。药敏结果表明对头孢噻肟、头孢曲松、头孢吡肟、氨曲南、阿米卡星、环丙沙星的敏感率分别为32.0%、4.0%、56.0%、36.0%、12.0%、48.0%,对头孢他啶、哌拉西林/三唑巴坦耐药率分别达56.0%和44.0%。随机将8株产CTX-M型ESBLs的肺炎克雷伯菌作PFGE分析,结果显示2株为相同的PFGE型,其它为不相关的PFGE型。结论产CTX-M型ESBLs肺炎克雷伯菌广泛分布于临床各科室,绝大多数菌株来自不同克隆株;多种基因型ESBLs的存在提高了它对抗生素的耐药水平。加强对产ESBLs细菌的检测及分子流行病学研究,对控制院内感染的流行十分重要。

Objective To analyze the epidemiology of CTX-M extended-spectrum β-lactamase （ESBLs） in clinical isolates of Klebsiella pneumoniae in Shantou. Methods For blaCTX-M gene in clinical isolates of Klebsiella pneumoniae PCR amplification were performed with specific primers of blacCTX-M and DNA analysis is by pulsed-field gel electrophresis （PFGE）, and the antibiotic resistance were determined. Results The prevalence of CTX-M ESBLs in clinical isolates of Klebsiella pneumoniae in Shantou was 30. 1% （25/83）, which of them were mainly isolated from sputum. The strains existed in different departments including neonatology center, respiratory, neurosurgery, neurology, pediatrics, surgery ICU ward, cardiosovasol and surgery. It was common that blaCTX-M coexistent with other genotypes in the same strain. The susceptibility rate to cefotaxime, cefatriaxone, cefepime, axthreonam, amikacin and tetracycline were 32.0%, 4.0%, 56.0%, 36.0%, 12.0% and 48.0% respectively. The resistance rate to ceftazidime and piperacillin/tazobactam were 56.0% and 44.0% respectively. The DNA analysis by PFGE in 8 random strains showed that there were 2 strians in the same type and others in different types. Conclusions The clinical isolates of Klebsiella pneumoniae producing CTX-M ESBLs existed in man）, departments. Most strains were isolated from different clones. The resistant level to antibiotics of the isolates were enhanced by more than one genotype-ESBLs. It is important to control nosocomial infection to strengthen the detection of the epidemiology of ESBLS in clinical isolates.