[北京腹泻患者分离出的致泻性大肠杆菌基因型及流行特征研究]

[Study on the genotype and epidemic characteristics of diarrheagenic Escherichia coli isolated from diarrheal patients in Beijing].

作者信息

Qu Mei, Zhang Xin, Qian Haikun, Lyu Bing, Huang Ying, Yan Hanqiu, Liang Zhichao, Jia Lei, Wang Quanyi

机构信息

Beijing Key Laboratory of Diagnostic and Traceability Technologies for Food Poisoning, Beijing Center for Disease Control and Prevention, Beijing 100013, China.

Beijing Key Laboratory of Diagnostic and Traceability Technologies for Food Poisoning, Beijing Center for Disease Control and Prevention, Beijing 100013, China. Email:

出版信息

Zhonghua Liu Xing Bing Xue Za Zhi. 2014 Oct;35(10):1123-6.

PMID:25567017

Abstract

OBJECTIVE

To understand the distribution of virulence gene and the epidemiological characteristics of diarrheagenic Escherichia(E.) coli (DEC) from diarrheal patients in Beijing.

METHODS

Stool specimens from diarrheal patients were cultured which were collected from the hospitals under sentinel surveillance program, during 2012-2013. DNA was examined by real-time PCR.

RESULTS

253 out of 6 370 specimens were positive for DEC detection with the rate as 4.0%. A total number of 262 DEC strains were isolated. Two different pathotypes of DEC strains with mixed infection, were isolated from 9 specimens. Different pathotypes would show the following profiles: 42.8% for enteropathogenic E. coli (EPEC) including 42.0% atypical and 0.8% typical; 38.9% for enterotoxigenic E. coli (ETEC) including 24.8% st positive, 9.9% lt positive and 4.2% st and lt both positive;15.3% for enteroaggregative E. coli(EAEC);2.7% for enteroinvasive E. coli (EIEC); one strain STEC with serotype O26:K60. ETEC had obvious characteristics on age. All kinds of DEC were isolated throughout the year with seasonal fluctuation.

CONCLUSION

DEC isolates from diarrheal patients in Beijing were dominated by EPEC and ETEC, with atypical ones accounted for the majority of EPEC. One specimen was found under mixed infection. Pathotypes DEC were found to have different age and seasonal distributions.

摘要

目的

了解北京地区腹泻患者中致泻性大肠埃希菌（DEC）毒力基因分布及流行病学特征。

方法

收集2012 - 2013年哨点监测医院腹泻患者粪便标本进行培养，采用实时荧光定量PCR检测DNA。

结果

6370份标本中253份DEC检测阳性，阳性率为4.0%，共分离出262株DEC菌株。从9份标本中分离出两种不同致病型的DEC菌株混合感染。不同致病型菌株构成比为：肠致病性大肠埃希菌（EPEC）占42.8%，其中非典型性EPEC占42.0%，典型性EPEC占0.8%；产肠毒素性大肠埃希菌（ETEC）占38.9%，其中耐热肠毒素（st）阳性占24.8%，不耐热肠毒素（lt）阳性占9.9%，st和lt均阳性占4.2%；肠集聚性大肠埃希菌（EAEC）占15.3%；肠侵袭性大肠埃希菌（EIEC）占2.7%；一株血清型为O26:K60的肠出血性大肠埃希菌（STEC）。ETEC在年龄上有明显特征。全年均有各类DEC分离，存在季节波动。