携带毒力岛大肠杆菌性小儿腹泻

Identification of high-pathogenicity island-harboring Escherichia coli from children with diarrhea disease

目的 探讨携带毒力岛大肠杆菌 (HPIEC)在小儿腹泻中的病原学地位。方法 采用PCR扩增和菌落原位杂交检测HPIEC irp2毒力岛基因 ,并用血清学分型和聚合酶链反应 (PCR)法检测各类致泻大肠杆菌。结果 从 10 32例腹泻患儿粪便中分离出 6 5 2株大肠杆菌 ,经血清学和PCR毒力基因分型 ,检出各类致泻大肠杆菌 2 2 5株 ,其中肠致病性大肠杆菌 (EPEC) 2 0株 ,ETEC 81株 ,产志贺样毒素大肠杆菌 (SLTEC) 4 7株 ,产志贺样毒素侵袭性大肠杆菌 (ESIEC) 74株 ,产毒素大肠杆菌 (EIEC)3株。所有致泻大肠杆菌和未能分型的普通大肠杆菌株 ,再用HPIEC irp2探针作菌落原位杂交 ,共检出携带毒力岛大肠杆菌 (HPIEC irp2 ) 112株 ,总阳性率为 17 2 %。其中 41株是从致泻大肠杆菌ESIEC(2 4/ 74)和SLTEC(17/ 47)中检出。携带毒力岛大肠杆菌性小儿腹泻的主要临床表现为食欲不振(87 5 % )、腹痛 (5 8 0 % )、腹泻 (>6次 /d ,75 9% )、发热 (5 0 9% )、以粘液便为主 (6 9 6 % )。结论 携带毒力岛大肠杆菌是引起小儿腹泻的重要病原菌之一。

Objective To investigate the etiological status of high pathogenicity island harboring Escherichia coli (HPIEC) in diarrhea diseases among children. Methods Escherichia coli was Isolated and identified from the stool specimens of 1 032 children with diarrhea diseases by culturing, serotyping, PCR, and colony hybridization. Results 652 strains of E.coli were isolated from the 1 032 stool specimens and confirmed by colony hybridization out of which 225 were identified as diarrheagenic E.coli , including 20 EPEC, 81 ETEC, 47 SLTEC, 74 ESIEC, and 3 EIEC strans. 112 (17.2%) irp2 virulent gene positive E.coli strains were detected from the 652 strains, out of which 24 were from the 74 ESIEC strans and 17 from the 47 SLTEC stranis. The typical clinical symptoms of diarrhea caused by HPI haboring E.coli included anorexia (87.5%), abdominal pain (58.0%), diarrhea (75.9%, over 6 episodes, mostly of mucous stool a day, 75.9%), and fever (50.9%). Conclusion High pathogenicity island harboring E.coli is one of the important pathogens of diarrhea diseases in children.