What Is Diarrhea? What Causes Diarrhea?

Editor's Choice
Main Category: GastroIntestinal / Gastroenterology
Also Included In: Infectious Diseases / Bacteria / Viruses;  Irritable-Bowel Syndrome;  Crohn's / IBD
Article Date: 23 Jul 2009 - 14:00 PDT

email to a friend   printer friendly   opinions  

Diarrhea is the frequent passing of loose or watery stools. Acute diarrhea, which is a common cause of death in developing countries, appears rapidly and may last from five to ten days. Chronic diarrhea lasts much longer and is the second cause of childhood death in the developing world. Diarrhea is sometimes accompanied by abdominal cramps or fever. It may be caused by infection, allergy, or could be a sign of a serious disorder, such as IBD (inflammatory bowel disease), or Crohn's disease.

According to the World Health Organization (WHO) approximately 3.5 million deaths each year are attributable to diarrhea. 80% of those deaths occur in children under the age of 5 years. Children are more susceptible to the complications of diarrhea because a smaller amount of fluid loss leads to dehydration, compared to adults.

A bacterium called enteroaggregative E. coli, is responsible for 10 percent of cases of diarrhea in children, researchers at Cincinnati Children's Hospital Medical Center, USA, found.

According to Medilexicon's medical dictionary, diarrhea is "An abnormally frequent discharge of semisolid or fluid fecal matter from the bowel."

What are the five types of diarrhea?

• Secretory diarrhea
  
  Either the gut is secreting more fluids than usual, or it cannot absorb fluids properly. In such cases structural damage is minimal. This is most commonly caused by a cholera toxin - a protein secreted by the bacterium Vibrio cholera.


• Osmotic diarrhea
  
  
  Too much water is drawn into the bowels. This may be the result of celiac disease, pancreatic disease, or laxatives. Too much magnesium, vitamin C, undigested lactose, or undigested fructose can also trigger osmotic diarrhea.


• Motility-related diarrhea
  
  Food moves too quickly through the intestines (hypermotility). If the food moves too quickly there is not enough time to absorb sufficient nutrients and water. Patients who had a vagotomy (removal or severing of the vagus nerve) as well as those with diabetic neuropathy are susceptible to this type of diarrhea.


• Inflammatory diarrhea
  
  The lining of the gut becomes inflamed. This is usually caused by bacterial infections, viral infections, parasitic infections, or autoimmune problems such as IBS (inflammatory bowel disease). Tuberculosis, colon cancer and enteritis can also cause inflammatory diarrhea.


• Dysentery
  
  The presence of blood in the stools is usually a sign of dysentery, rather than diarrhea. Dysentery is caused by a release of excess water caused by an antidiuretic hormone from the posterior pituitary gland. Dysentery is one of the symptoms of Shigella, Entamoeba histolytica, and Salmonella.

When it occurs in people age 60 and older, there's a good possibility bloody diarrhea indicates ischemic colitis, according to the Mayo Clinic, USA.

What are the symptoms of diarrhea?

Some sufferers may pass slightly watery stools and have brief episodes of stomachache, while others may pass very watery stools and have more severe stomach cramping. The most common symptoms include:

• Abdominal cramps
• Abdominal pain
• An urge to go to the toilet, sometimes this may be sudden
• Vomiting
• Nausea
• Temperature (fever)
• Headache
• Loss of appetite
• Fatigue
• Loose, watery stools
• Bloating
• Blood in stool

Anybody who has had diarrhea for more than one week should see their doctor. The UK National Health Service advises parents to take their child to the doctor if:

• The child is aged 3 months to 1 year and the diarrhea has lasted over two days
• The child is over 1 year of age and the diarrhea has lasted more than five days

You should also see your doctor if you experience or witness any of the following:

• You have symptoms of dehydration - excessive thirst, very dry mouth, very little or no urination
• Your abdominal pain is severe
• You have severe rectal pain
• There is blood in the stools, the stools are black
• Your temperature is over 39C (102 F)
• A baby has not wet the diaper (UK: nappy) in over three hours
• A child/baby is very sleepy, irritable, or unresponsive
• A child/baby has a sunken abdomen
• A child/baby has sunken eyes and/or cheeks
• The child's/baby's skin does not flatten after being pinched

What causes diarrhea?

Causes of acute diarrhea (short term diarrhea)

This is usually caused by an infection, and is also a symptom of a bowel infection when the stomach and the intestines become inflamed (gastroenteritis). This may be caused by:

• A virus - most commonly a norovirus or a rotavirus. It could also be caused by a hepatitis virus, or the herpes simplex virus. Viral diarrhea spreads easily.


• A bacteria - if food or water is contaminated bacteria and parasites can be transmitted into the body. Parasites may include Giardia lamblia and cryptosporidium. Examples of bacteria are campylobacter, salmonella, shigella and Escherichia coli (E. coli). Traveler's diarrhea is usually caused by bacteria or parasites. Researchers at Boston University School of Medicine identified the structure of bacteria responsible for traveler's diarrhea.


• An antibiotic - antibiotics can disturb the natural balance of bacteria in our intestines, which can lead to infection, commonly with a bacterium called Clostridium difficile.

The following may also be causes of acute diarrhea:

• Anxiety
• Consuming too much alcohol
• Consuming too much coffee
• Some other medications, apart from antibiotics

Causes of chronic diarrhea (persistent, longer term diarrhea)

• Bacteria
• A virus
• Laxatives
• Some dietary habits - long term regular alcohol, coffee consumption may cause persistent diarrhea. Regular eating of candy (sweets) can too. Many sugar-free chewing gums containing a sweetener called sorbitol can cause chronic diarrhea, The British Medical Journal reported.

The following long-term conditions can cause chronic diarrhea

• Celiac disease
• Crohn's disease
• Diabetes
• Irritable bowel syndrome (IBS)
• Lactose intolerance
• Pancreatitis
• Ulcerative colitis

How is diarrhea diagnosed?

Most cases of acute diarrhea will resolve themselves within a week or so. If the diarrhea lasts longer, or if there is blood in the stools and there are other symptoms, such as dehydration, the GP (general practitioner, primary care physician) will take a stool sample to check for infection.

A sigmoidoscopy may also be performed. This involves introducing a thin fiber-optic tube through the rectum to look into the intestine. The device has a viewing lens.

The doctor will also ask the patient whether he/she is taking any medications, has traveled recently, and possibly some questions about what foods were consumed over the last couple of weeks. The GP may also examine the abdomen to determine where the pain is.

What is the treatment for diarrhea?

In the vast majority of cases the diarrhea will disappear within a week or so. Before it does, the following steps may help ease symptoms:

• Drink plenty of fluids - diarrhea often carries a risk of dehydration, especially if it includes vomiting. It is important to make sure babies and children are getting plenty of fluids.
  
  Diarrhea may affect the balance of salts and electrolytes in the body. Special dehydration drinks can be bought in a pharmacy to restore their balance. A pharmacist can advise on which drinks to consume.


• Eat as soon as you feel up to it - doctors used to tell people not to eat until the symptoms went away. They now recommend patients start with foods such as pasta, bread, rice or potatoes - foods high in carbohydrates, as soon as possible. Add a bit of salt to the food to replace salt loss. Avoid foods that are high in fat.


• Medications - such medicines as loperamide may slow down bowel movements and may also increase the gut's water absorption. Do not give anti-diarrhea medications to children without checking first with a doctor. Do not take anti-diarrhea medications if there is blood in the stools or if you have a fever.


• Breastfeeding or bottle-feeding babies - doctors recommend that feeding continue as normal if the baby has diarrhea. If necessary, add rehydration drinks that are bought from a pharmacy.


• Painkillers - for fever or headache doctors recommend Tylenol (paracetamol) or ibuprofen. If you have kidney, liver or long-term stomach problems do not take ibuprofen. Do not give aspirin if your child is under 16 years of age.


• Probiotics - these are supposed to treat diarrhea, among other things. However, a study published in the British Medical Journal indicated that some of them don't work, while others do.

Doctors may prescribe specific medications, depending on the results of the stool test.

How can you lower your risk of developing diarrhea?

Hand washing - regular hand-washing with soap and warm water helps reduce the risk of catching or passing on germs. Especially after going to the toilet, playing with pets, gardening, and before touching food. An intensive program of handwashing education and promotion in Pakistan decreased the incidence of diarrhea by more than 50 percent among children, according to a study.

Keeping the kitchen and toilets as clean as possible also reduces the risk. When handling raw meats wash your hands before touching other things, such as other foods, work surfaces, cutlery, etc.

If you are travelling to a warm country remember that uncooked foods are more likely to have bacteria than hot food. Depending on where you are, it is sometimes advisable to avoid having ice in your drinks if you are not sure where the water to make the ice came from.

Sources: National Health Service (NHS), UK, The Mayo Clinic, Wikipedia, HHS (Department of Health and Human Services USA), NIH (National Institutes of Health, USA).

Written by Christian Nordqvist
Copyright: Medical News Today
Not to be reproduced without permission of Medical News Today

• Additional
• References
• Citations