DIARRHEA

Diarrhea is a very common phenomenon in both adults and children. It is manifested by an increase in stool weight (over 200g per day), fluidity (water content over 85%) and frequency of stools (over three per day). Often, it causes flatulence and an urgent need to void.

Depending on the duration, diarrhoea is classified as follows:

• • • Acute diarrhea: Has a sudden onset and lasts up to 14 days. Diarrhoea may have an onset of diarrhoea lasting up to 14 days to 14 days, but is mild and resolves quickly without complications and may be particularly severe in children under 3 years of age. Acute diarrhoea is usually due to viral or bacterial infections. In adults it occurs on average four times a year and is mild and short-lived. In children, however, it can have serious complications.
    • Chronic diarrhoea: Has a duration of more than 14 days. It is usually due to functional disorders such as irritable bowel syndrome, celiac disease or inflammatory bowel disease.

Diarrhea may contain mucus, pus or blood, depending on the cause, and may be accompanied by fever, abdominal pain, nausea, vomiting and general malaise.

GASTROENTERITIS

The most common cause of acute diarrhoea is gastroenteritis, an infection of the digestive tract caused by bacteria, parasites or, more commonly, viruses.

Viral gastroenteritis is caused by noroviruses, rotaviruses, asteroviruses and adenoviruses. Rotovirus usually infects children, who then develop antibodies and immunity as adults. Adults are more commonly affected by norovirus, which is very resistant to the environment and thus easily transmitted through infected surfaces. Norovirus patients are infectious for up to three days after recovery. Symptoms usually pass on their own after 2-3 days, but can last up to 10 days.

Gastroenteritis caused by bacteria (food poisoning) is often associated with eating contaminated food that has not been adequately cooked and/or left out of the refrigerator for hours. It is usually more severe than viral, lasts longer and is sometimes accompanied by blood in the stools and a high fever. In developed countries it is usually caused by Campylobacter jejuni, Escherichia coli, Salmonella, Sigella and Campylobacter. Those travelling to Eastern Europe, South Africa and the Caribbean are at some risk of contracting E. Coli. The risk is increased in travelers to Asia, Middle East, Africa, Central and South America.

Clostridium difficile most commonly affects older people, causing diarrhoea. Bacterial gastroenteritis of any form usually goes away on its own, although antibiotics may be needed in some cases. Diarrhoea is secretory, i.e. caused by excessive secretion of water and salts in the gut.

Parasites – most commonly Giardia lamblia – also cause diarrhoea. They are responsible for 10% of cases in children.

Gastroenteritis can cause persistent diarrhoea and vomiting affecting children and adults. Patients may also experience nausea, abdominal pain and cramps, headache, muscle aches, fatigue, chills and rarely fever. The fever is generally low. Because of the cold and the fact that people stay indoors, transmission is more common from the winter months until spring.

For most people viral gastroenteritis is not a serious disease. Patients almost always make a full recovery without further health problems. However, infants, young children, people with disabilities, people who cannot help themselves, the elderly, and immunocompromised people may need hospitalisation to treat possible dehydration. In case of dehydration, a person may have decreased urination, dry mouth and dizziness. A dehydrated child may cry with few or no tears and have unusual drowsiness. Death from the disease is extremely rare but the disease can aggravate any pre-existing health problems.

PATHOGENS CAUSING DIARRHOEA

Some substances naturally absorb water. If these substances are not absorbed by the body and if they are found in the gastrointestinal tract, the osmotic effect is caused – i.e. they absorb fluid from the walls of the intestine which is expelled in the stool, causing watery diarrhoea. This can occur with some antacids or hypertonic drugs, in sorbitol, in cases of lactose intolerance and fat malabsorption.

When there is damage to the intestinal mucosa leading to the release or leakage of mucus, blood and plasma proteins from the cells as a result of inflammation, exudative diarrhoea results. It is usually the result of the presence of an inflammatory condition, such as Crohn’s disease or ulcerative colitis.

Finally, rapid intestinal transit diarrhea results from an increase in propulsive activity in the colon. When the colon contracts more strongly than normal, food passes more quickly through the digestive tract and less water is absorbed back into the body, making the stool very watery. Causes of this type of diarrhea include irritable bowel syndrome, surgical bypass, gastric and intestinal resections, antibiotics or stress.

Diarrhoea can also be caused by antibiotic drugs, which destroy the gut microbiome, by immunodeficiency or even by increased stress and anxiety, which causes stimulation of bowel activity.

Source: ZARBIS Scientific library