Gastrointestinal Conditions and Diseases

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Due to constant mechanical trauma and exposure to pathogens and toxic substances, the gastrointestinal system can take a serious beating over a lifetime. Gastrointestinal concerns are extremely common, with the most frequent complaints being abdominal pain, gastrointestinal bleeds, nausea and vomiting, malabsorption, and diarrhea, and jaundice.

Common causes for these signs and symptoms are listed below.

  • Esophagus
  • Stomach
  • Intestines
  • Liver
  • Pancreas
  • Gall Bladder


Stomach Conditions and Diseases


Intestinal Conditions and Diseases


to clean up:

Small Intestine

The small intestine is colonized with many bacteria, fungi, and parasites. Most of these are anaerobes, such as Peptostreptococcus, Porhyromonas, and Prevotella. Small numbers of Samonella and Campylobacter can be present asymptomatically. Intestinal stasis can lead to colonization and invasion by organisms normally associated with the colon, leading to malabsorptive syndromes.


Large Intestine

More microbes are found in the large intestine than anywhere else in the body - it is estimated that there are more than 1011 bacteria per gram of stool. Anaerobic bacteria are in excess of more than 1000 fold, with the most common being Bifidobacterium and Eubacterium. These bacteria rarely cause disease.

While enterobacteriacae such as Escherichia coliaccount for less than 1% of the bacterial population, it accounts for most intra-abdominal disease.

Various yeasts and non-pathogenic parasites also are present.

Antibiotic treatment can rapidly change the bacterial population in the colon, leading to proliferation of antibiotic-resistant organisms such as Pseudomonas, enterococci, fungi, and C. difficile.




Viral gastroenteritis is one of the top 5 causes of pediatric admission to hospital.

There are now dipsticks available to screen stool for rotavirus, adenovirus, and norovirus, wher

adenovirus can cause diarrhea



Pancreas Conditions and Diseases



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