Department of Gastrointestinal Sciences, Christian Medical College, Vellore, India.
Diagn Microbiol Infect Dis. 2010 Oct;68(2):117-22. doi: 10.1016/j.diagmicrobio.2010.06.003.
The prevalence of diarrheagenic Escherichia coli (DEC) in children under 5 years was studied in children with diarrhea and controls in South India. Four polymerase chain reaction (PCR) "schemes" were used to detect genes of the 6 pathotypes of DEC. In 394 children with diarrhea, 203 (52%) DEC infections were found. Among the 198 controls, 126 (63%) DEC infections were found. Enteroaggregative E. coli was the most common pathotype by multiplex PCR both in cases (58, 14.7%) and controls (47, 23.7%), followed by enteropathogenic E. coli seen in 10% cases and 8% of controls. Enterotoxigenic E. coli (ETEC), enterohemorrhagic E. coli (EHEC), enteroinvasive E. coli (EIEC), and diffusely adherent E. coli (DAEC) were found in 4.1%, 2.0%, 1.0%, and 0.5% of cases, respectively. ETEC was found in 2.5% of controls, but EHEC, EIEC, and DAEC were not detected. Overall, no single assay worked well, but by discounting genes with a pathogenicity index of less than 1, it was possible to use the PCR assays to identify DEC in 75/394 (19%) cases and 12/198 (6.1%) controls, while mixed infection could be identified in 8/394 (2%) cases and 2/198 (1%) controls.
在印度南部,研究了 5 岁以下儿童腹泻患者和对照者中腹泻性大肠埃希菌 (DEC) 的流行情况。使用 4 种聚合酶链反应 (PCR) “方案”来检测 6 种 DEC 病原体的基因。在 394 名腹泻儿童中,发现了 203 例(52%)DEC 感染。在 198 名对照者中,发现了 126 例(63%)DEC 感染。在病例和对照者中,多重 PCR 显示肠聚集性大肠埃希菌均为最常见的病原体型(58 例,14.7%;47 例,23.7%),其次是 10%的病例和 8%的对照者中可见肠致病性大肠埃希菌。肠毒性大肠埃希菌(ETEC)、肠出血性大肠埃希菌(EHEC)、肠侵袭性大肠埃希菌(EIEC)和弥漫黏附性大肠埃希菌(DAEC)分别在 4.1%、2.0%、1.0%和 0.5%的病例中发现。在对照者中发现了 2.5%的 ETEC,但未检测到 EHEC、EIEC 和 DAEC。总体而言,没有单一的检测方法效果良好,但通过排除致病性指数小于 1 的基因,可以使用 PCR 检测方法在 75/394 例(19%)病例和 12/198 例(6.1%)对照者中识别 DEC,同时可以在 8/394 例(2%)病例和 2/198 例(1%)对照者中识别混合感染。