What is gastroenteritis?

Gastroenteritis is the inflammation of the stomach, small and large intestine. The most common cause of gastroenteritis is due to the action of microbes or toxins, which irritate the lining in these areas of the gastrointestinal tract (gut) and affect nutrient absorption, trigger the process of inflammation and may lead to ulceration of the lining. A rare case of gastroenteritis known as eosinophilic gastroenteritis is associated with allergies and also cause inflammation of the stomach and small intestine. This results in the typical symptoms of nausea, vomiting, diarrhea and abdominal pain.

Acute Gastroenteritis

Infectious

Most cases of gastroenteritis are due to infections which are often acute in nature and will resolve spontaneously without treatment. Infectious gastroenteritis is known by many other common names like the stomach bug or gastric flu and is a result of an infection with a bacteria, viruses or protozoa. The incubation period may vary from a few hours in bacterial infections to a few days in viral gastroenteritis, while protozoal infections can take weeks before the onset of symptoms.

At times, medical intervention may be necessary but this should only be considered when the causative organism has been identified and if the infection is not resolving. The symptoms of acute gastroenteritis are very intense with extreme nausea, violent vomiting and explosive diarrhea accompanied by severe abdominal pain being a typical presentation of infectious gastroenteritis. A fever is usually present.

Non-Infectious

Non-infectious causes like bacterial toxins, certain drugs (including chemotherapy), radiation therapy, poisoning and environmental toxins may also cause acute gastroenteritis. These cases of gastroenteritis may resolve once the causative factor is removed or expelled from the gut.

Chronic Gastroenteritis

Less frequently, a case of infectious gastroenteritis can be persistent – chronic in nature.  A chronic case of infectious gastroenteritis is more likely to occur in an immunocompromised patient as is the case in HIV/AIDS (opportunistic infections) or a poorly managed chronic condition like diabetes.

A malabsorption syndrome is often a result of chronic gastroenteritis, irrespective of the cause, and leads to mineral and vitamin deficiencies.

Allergic

Eosinophilic gastroenteritis is another cause of chronic gastroenteritis but this condition is rare. It is closely related to other immune mediated conditions like hay fever, asthma and eczema (the allergic triad), especially in children. Food allergies are common in these conditions. Eosinophilic gastroenteritis is an inflammatory condition that affects the stomach and often the small intestine as well. A high concentration of eosinophils, a type of white blood cell, is found in the mucosal lining of the stomach and small intestine and these leukocytes play an important role in allergies.

Foods that Cause Gastroenteritis

Food infection is a term commonly used to describe food borne illnesses, where the microbe infects the host rather than by causing disease through toxins in the food (food poisoning or food intoxication). The most common foodborne illness is gastroenteritis but other diseases like Creutzfeldt-Jakob disease (CJD or “Mad Cow”disease) are also foodborne illnesses.

Although the term foodborne may indicate that it is only present in foods, waterborne illnesses may also be contracted in foods because contaminated water may be used for washing meat, fruits and vegetables that are eaten raw. Traveler’s should be aware of these foodborne diseases as it is a common cause of traveler’s diarrhea.

Food Sources

  • Shigella spp may be present in any food.

Canned Goods

  • Clostridium botulinum

Cheese (Unpasteurized)

  • Campylobacter spp
  • Enterotoxicogenic E.coli (ETEC)
  • Listeria monocytogenes
  • Salmonella spp
  • Yersinia enterocolitica

Eggs (Raw)

  • Salmonella spp

Meat (Beef, Pork) and Poultry (Chicken, Duck)

  • Campylobacter spp
  • Clostridium perfringens
  • Enterohemorrhagic E.coli (EHEC)
  • Listeria monocytogenes – hot dogs, vienna sausages, pate
  • Salmonella spp
  • Staphylococcus spp

Milk (Unpasteurized) or Juice

  • Campylobacter spp
  • Enterohemorrhagic E.coli (EHEC)
  • Salmonella spp
  • Staphylococcus spp
  • Yersinia enterocolitica

Rice

  • Bacillus spp

Seafood (Raw)

  • Aeromonas spp
  • Astrovirus
  • Norovirus
  • Plesiomonas spp
  • Vibrio spp

Vegetables

  • Aeromonas spp
  • Clostridium perfringens

Article reviewed by Dr. Greg. Last updated on September 9, 2012