Enteric Pathogens

Most intestinal bacterial infections are caused by enteric pathogens. The clinical symptoms usually associated with the intestinal infections include fever, abdominal pain and diarrhea. Enteric bacteria are capable of evading host defense factors such as gastric acidity, intestinal motility, the normal indigenous microbiota, mucus secretion, and specific mucosal and systemic immune mechanisms.

In order for ingested pathogenic bacteria to infect the colon, they produce virulence factors. Enteric bacteria can be divided into four main categories based on the virulence factors that enable them to overcome the host defense. The first group of bacterial pathogens consists of Campylobacter jejuni, Yersinia enterocolitica, Shigella and Salmonella species. Their mechanism of virulence involves the mucosal invasion with intraepithelial cell multiplication resulting in cell death. The second group comprises enteric pathogens that produce cytotoxins which will in turn cause cell injury and inflammation. Microorganisms that produce cytotoxins include Clostridium difficile, enteropathogenic Escherichia coli (EPEC) and enterohemorrhagic E. coli (EHEC). The third class of pathogens secretes enterotoxins which will alter intestinal salt and water balance without affecting mucosal morphology. Vibrio cholerae, Shigella and enterotoxigenic E. coli produce such enterotoxins. The last category of enteric pathogens can only cause disease when they tightly adhere to the intestinal surface. The classic enteropathogenic E. coli as well as the enteroadherent E. coli is typical of this group. Both the small intestine and colon are primary sites for enteroadhesion (18).

Pregnancy And Childbirth

Pregnancy And Childbirth

If Pregnancy Is Something That Frightens You, It's Time To Convert Your Fear Into Joy. Ready To Give Birth To A Child? Is The New Status Hitting Your State Of Mind? Are You Still Scared To Undergo All The Pain That Your Best Friend Underwent Just A Few Days Back? Not Convinced With The Answers Given By The Experts?

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