太原地区携带OI-28毒力基因组岛致泻大肠埃希菌性小儿腹泻

Detection of diarrheagenic Escherichia coil harboring genomic O island 28 isolated from children diarrhea in Taiyuan

目的探讨携带OI-28毒力基因组岛致泻大肠埃希菌在小儿腹泻中的病原学作用。方法在山西省儿童医院采集257例腹泻病患儿粪便，做肠道病原菌常规培养和致泻大肠埃希菌血清学分型鉴定，用PCR和DNA斑点杂交检测致泻大肠埃希菌EHECOI-28毒力基因组岛中与RTX相关的5个毒力基因。结果257例腹泻病患儿检出病原菌206株（80．16％）。其中大肠埃希菌149株（57．98％），其他肠道致病菌57株（22．18％）。血清分型检出致泻大肠埃希菌EPEC3株（2．01％）、ETEC2株（1．34％）、EHEC2株（1．34％），其余142株为“疑似致泻大肠埃希菌”（55．25％）。149株大肠埃希菌中OI-28 5个基因全阳性者21株（14．09％），1个基因阳性者8株（5．37％），2个基因阳性者2株（1．34％）。21例携带OI-28毒力基因组岛大肠埃希菌感染的腹泻患儿，以3岁以下小儿为主（80．95％）。结论携带OI-28毒力基因组岛大肠埃希菌是夏季小儿腹泻的重要病原菌之一。

Objective To investigate the etiologic value of diarrheagenic E. coil harboring genomic O island 28（OI-28） containing five putative virulence genes（ Z0608, Z0609, Z0615, Z0634 and Z0635）, which were related to RTX （Repeat in toxin） toxin family isolated from children with diarrheal disease in Taiyuan. Methods In the study,257 fecal samples from children with diarrheal disease collected in Shanxi Children＇s Hospital. Diarrheagenic E. coli and enteropathogenic bacteria were isolated and identified by conventional bacterial culture and typing specific diarrheagenic E. coli （EPEC, EIEC, ETEC and EHEC） diagnostic serum, while diarrheagenic E. coli harboring genomic OI-28 containing five putative virulence genes（Z0608, Z0609, Z0615, Z0634 and Z0635） were detected by PCR and DNA southern blot hybridization. Results 206 strains（80.16% ） of enteropathogenic bacteria were detected from 257 children with diarrhea dlsease,containing 149 strains（57.98% ） of diarrheagenic E. coli and 57 strains（22.18% ） of other entero-pathogenic bacteria. Among 3 strains （2.01% ） of EPEC, 2 strains （ 1.34 % ） of ETFC, 2 strains（1.34% ） EHEC were detected by typing specific serum, while all of the 142 strains （95.30%） isolated were suspected to be diarrheagenic E. coli. 21 strains（14.09 % ） of diarrheagenie E. coil harboring genomie OI-28 containing five putative virulence genes （ Z0608, Z0609, Z0615, Z0634 and Z0635） were detected by polymerase chain reaction and DNA southen blot hybridization, 8 strains （5.37%） of diarrheagenic E. coli containing only one genomic OI-28 virulence gene,2 strains（ 1.34 % ） of diarrheagenic E. coli containing two genomic OI-28 virulence gene. 21 children with diarrhea diseases caused OI-28- harboring E. coli containing five important putative virulence genes were among 0 to 3 years old （80.95%）. These children correlating with OI-28-harboring E. con did not present special cbnical symptoms or signs. Conclusion The diarrheagenic E. coil harboring genomic OI-28 was one of the important etiology for children with diarrheal disease in summer season.