Molecular detection of new type of Escherichia coli in pediatric patients

Share on facebook
Share on google
Share on twitter
Share on linkedin
Illustration by

Diarrhea is a common cause of death in developing countries and the second leading cause of death in infants throughout the world. Some infectious diarrheal diseases are caused by viruses, bacteria, and parasites. Bacteria cause about 15% of cases in children, with the most common type being E. coli. Most strains of E. coli are harmless, but some pathogenic serotypes can cause serious food poisoning and diarrhea in humans.

Diarrheal causing E. Coli is found everywhere in the world. E. coli is classified based on its virulence characteristics; each group causes disease through different mechanisms. Pathogenetic E. coli is classified into five virotypes, (1) Enterotoxigenic E. coli (ETEC) produces exotoxin that is not heat resistant (LT) and enterotoxin that is heat resistant (ST). (2) Enteropathogenic E. coli (EPEC) adheres to epithelial cells very well, excretes adhesions or removes wounds and irritates but does not release toxins. (3) Enterohemorrhagic E. coli (EHEC) produces shiga toxin / verotoxin, named for its cytotoxic effect on vero cells, an African monkey kidney. (4) Enteroaggregative E. coli (EAEC) is characterized by its characteristic adhesion pattern in humans and produces ST-like toxins and hemolysin. (5) Enteroinvasive E. coli (EIEC) does not ferment lactose and produces disease by invading intestinal mucosal epithelial cells.

Initial research on genetic analysis shows that this bacterial strain is a mutant form of two E coli bacteria , enteroaggregative E coli (EAEC) and enterohemorrhagic E coli (EHEC) called Enteroaggregative Hemorrhagic E coli (EAHEC).

So far there are several methods to determine the presence of E. coli from stool samples and to differentiate it from other enteropathogenic bacteria as well as from other strains of E. coli , such as serological testing. However, this method has weaknesses and limitations, such as being less specific because there will be cross-reactions with antibodies from other bacteria. Meanwhile, each strain of E. coli has certain specific genes that differentiate it from other strains of bacteria. Molecular methods by means of bacterial DNA amplification such as PCR can precisely detect these specific genes, so that they can be used to carry out molecular detection of E. coli strain.

With this research, it was found that the incidence of diarrhea in children under five at RSUD Dr. Soetomo Surabaya caused by Enteroagregative Hemorrhagic E. coli (EAHEC) is a new strain of E. coli which is very deadly because it produces more dangerous toxins so anticipation should be planned to solve the case. The development of a more sensitive primer to detect Hemorrhagic Enteroaggregative E. coli (EAHEC) bacteria should be done.

In this study, the sample was 40 feces samples of all children under five (aged 1-5 years) who were treated at Dr. Soetomo Surabaya who experienced diarrhea in 2015. Sampling was carried out by medical personnel at Soetomo Surabaya Hospital using rectal tubes and sterile container tubes. All stool samples were collected in sterile containers and cultured immediately in less than 2 hours after sampling. Then PCR test was carried out for molecular detection. The exclusive criteria for the sample was that patients have not taken antibiotics, so the bacteria causing diarrhea were still present in the feces and can be detected.

Based on the results of the above research, it can be concluded that the Enteroaggregative Hemorrhagic E. coli (EAHEC) bacteria was one of the causes of diarrhea in children under five at Dr. Soetomo Surabaya. There was 7.5% diarrhea caused by Enteroagregative Hemorrhagic E. Coli (EAHEC) in children under five at Dr. Soetomo Surabaya.

The discovery of a new E. coli strain, Enteroaggregative Hemorrhagic E. coli (EAHEC) can be used as a reference for medical personnel and related parties to carry out more specific treatment so the diarrhea caused by the Enteroaggregative Hemorrhagic E. coli (EAHEC) bacteria would not spread. It is expected that in further research, the sequencing test will be continued to determine the phylogenetic tree of the Enteroaggregative Hemorrhagic E. coli (EAHEC) as well as further studies on the development of a more specific primer for molecular detection of Enteroaggregative Hemorrhagic E. coli (EAHEC) bacteria.

Authors: Dr. Dadik Raharjo and Wahyu Setyarini Details of this research can be viewed on:

Related News



Media komunikasi dan informasi seputar kampus Universitas Airlangga (Unair).

Leave Replay

Close Menu