Molecular Biology Unit, Pasteur Institute of Iran, Tehran, Iran.
Braz J Infect Dis. 2011 Jul-Aug;15(4):365-9. doi: 10.1016/s1413-8670(11)70206-9.
Enteropathogenic Escherichia coli (EPEC) comprise one of the six categories of diarrhoeagenic E. coli (DEC). EPEC is subgrouped into typical (tEPEC) and atypical (aEPEC). The identification of DEC cannot be based only on cultural and biochemical criteria, since they are indistinguishable from the non-pathogenic E. coli commonly found in human feces. Several PCR methods, with both single and multiple target genes, have been reported for detecting the different DEC pathotypes. In the present study five hundred E. coli isolates from children with diarrhea were subjected into multiplex PCR. Furthermore the strains were typed serologically with O antisera and their fliC gene was characterized by PCR-RFLP. The results obtained revealed that overall 41 (8.2%) isolates could be detected as EPEC by this multiplex PCR assay. Of these isolates; 27 (66%) were typical (escv+, bfp+) and 14 (34%) atypical EPEC (escv+, bfp-). None of these 41 isolates contained the Stx1 and Stx2 genes. Among 37 (90%) typeable strains, nine different serogroups were present. The most common serogroups were O111, followed by O86, O55 and O119 and 10 different H types were found among these isolates. The multiplex PCR assay was found to be rapid and reliable in comparison to serological test; especially when screening the large number of isolates.
肠致病性大肠杆菌（EPEC）是六种致泻性大肠杆菌（DEC）之一。EPEC 可分为典型（tEPEC）和非典型（aEPEC）。DEC 的鉴定不能仅基于文化和生化标准，因为它们与人类粪便中常见的非致病性大肠杆菌无法区分。已经报道了几种使用单个或多个靶基因的 PCR 方法来检测不同的 DEC 病原体。在本研究中，对 500 株来自腹泻儿童的大肠杆菌分离株进行了多重 PCR。此外，这些菌株还通过 O 抗血清进行血清学分型，并用 PCR-RFLP 对其 fliC 基因进行了特征分析。结果表明，总体而言，500 株分离株中有 41 株（8.2%）可通过该多重 PCR 检测为 EPEC。其中 27 株（66%）为典型（escv+，bfp+），14 株（34%）为非典型 EPEC（escv+，bfp-）。这些分离株均未携带 Stx1 和 Stx2 基因。在 37 株（90%）可分型的菌株中，存在 9 种不同的血清型。最常见的血清型是 O111，其次是 O86、O55 和 O119，这些分离株中发现了 10 种不同的 H 型。与血清学检测相比，多重 PCR 检测法更快、更可靠；特别是在筛选大量分离株时。
