Diarrhea

What is diarrhea? 

It 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."


Five types of Diarrhea

• 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.

• 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 bacteriumVibrio cholera.

• 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 diarrhea

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.


Symptoms


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 ahepatitis 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 andcryptosporidium. Examples of bacteria are campylobacter, salmonella, shigellaand 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 calledClostridium 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.


How is diarrhea treated?

Absorbents. Absorbents are compounds that absorb water. Absorbents that are taken orally bind water in the small intestine and colon and make diarrheal stools less watery. They also may bind toxic chemicals produced by bacteria that cause the small intestine to secrete fluid; however, the importance of toxin binding in reducing diarrhea is unclear.

The two main absorbents are attapulgite and polycarbophil, and they are both available without prescriptions.

Examples of products containing attapulgiteare:

• Donnagel,
  
• Rheaban,
  
• Kaopectate Advanced Formula,
  
• Parepectolin, and
  
• Diasorb.

Examples of products containing polycarbophil are:

• Equalactin,
  
• Konsyl Fiber,
  
• Mitrolan, and
  
• Polycarb.

Equalactin is the antidiarrheal product containing attapulgite; however the laxative, Konsyl, also contains attapulgite. Attapulgite and polycarbophil remain in the intestine and, therefore, have no side effects outside of the gastrointestinal tract. They may occasionally cause constipation and bloating. One concern is that absorbents also can bind medications and interfere with their absorption into the body. For this reason, it often is recommended that medications and absorbents be taken several hours apart so that they are physically separated within the intestine.

Anti-motility medications. Anti-motility medications are drugs that relax the muscles of the small intestine and/or the colon. Relaxation results in slower flow of intestinal contents. Slower flow allows more time for water to be absorbed from the intestine and colon and reduces the water content of stool. Cramps, due to spasm of the intestinal muscles, also are relieved by the muscular relaxation.

The two main anti-motility medications are loperamide (Imodium), which is available without a prescription, and diphenoxylate (Lomotil), which requires a prescription. Both medications are related to opiates (for example, codeine) but neither has the pain-relieving effects of opiates.

Loperamide (Imodium), though related to opiates, does not cause addiction.

Diphenoxylate is a man-made medication that at high doses can be addictive because of its opiate-like, euphoric (mood-elevating) effects. In order to prevent abuse of diphenoxylate and addiction, a second medication, atropine, is added to loperamide in Lomotil. If too much Lomotil is ingested, unpleasant side effects from too much atropine will occur.

Loperamide and diphenoxylate are safe and well-tolerated. There are some precautions, however, that should be observed.

• Anti-motility medications should not be used without a doctor's guidance to treat diarrhea caused by moderate or severe ulcerative colitis, C. difficile colitis, and intestinal infections by bacteria that invade the intestine (for example, Shigella). Their use can lead to more serious inflammation and prolong the infections.

• Diphenoxylate can cause drowsiness or dizziness, and caution should be used if driving or performing tasks that require alertness and coordination are required.

• Anti-motility medications should not be used in children younger than two years of age.

• Most unimportant, acute diarrhea should improve within 72 hours. If symptoms do not improve or if they worsen, a doctor should be consulted before continuing treatment with anti-motility medications.

Bismuth compounds. Many bismuth-containing preparations are available around the world. Bismuth subsalicylate (Pepto-Bismol) is available in the United States. It contains two potentially active ingredients, bismuth and salicylate (aspirin). It is not clear how effective bismuth compounds are, except in traveler's diarrhea and the treatment of H. pylori infection of the stomach where they have been shown to be effective. It also is not clear how bismuth subsalicylate might work. It is thought to have some antibiotic-like properties that affect bacteria that cause diarrhea. The salicylate is anti-inflammatory and could reduce secretion of water by reducing inflammation. Bismuth also might directly reduce the secretion of water by the intestine.

Pepto-Bismol is well-tolerated. Minor side effects include darkening of the stool and tongue. There are several precautions that should be observed when using Pepto-Bismol.

• Since it contains aspirin, patients who are allergic to aspirin should not take Pepto-Bismol.

• Pepto-Bismol should not be used with other aspirin-containing medications since too much aspirin may be ingested and lead to aspirin toxicity, the most common manifestation of which is ringing in the ears.

• The aspirin in Pepto-Bismol can accentuate the effects of anticoagulants, particularly warfarin (Coumadin), and lead to excessive bleeding. It also may cause abnormal bleeding in people who have a tendency to bleed because of genetic disorders or underlying diseases, for example, cirrhosis, that may cause abnormal bleeding.

• The aspirin in Pepto-Bismol can aggravate stomach and duodenal ulcer disease.

• Pepto-Bismol and aspirin-containing products should not be given to children and teenagers with chickenpox, influenza, and other viral infections because they may cause Reye's syndrome. Reye's syndrome is a serious illness affecting primarily the liver and brain that can lead to liver failure and coma, with a mortality rate of at least 20%.

• Pepto-Bismol should not be given to infants and children younger than two years of age.

• Diarrhea Prevention

  Many cases of diarrhea are spread from person-to-person. The following precautions can help an individual avoid diarrhea and other viral or bacterial infections:
  • Individuals caring for sick children or adults in any setting should carefully wash their hands after changing diapers, helping an individual use the bathroom, or assisting an individual around the home.
    
  • Children should be instructed to wash their hands frequently, especially after using the bathroom.
  Practice safe food-handling. Always wash hands before and after handling food.
  • Use care when preparing raw poultry or meat. Food should be cooked to the recommended temperatures. Avoid raw or rare meat and poultry. Utensils coming in contact with raw food should be cleaned in soap and hot water.
    
  • Fruits and vegetables consumed raw should be thoroughly rinsed in clean water.
    
  • Unpasteurized (raw) milk may be contaminated with bacteria and should always be avoided. Unpasteurized fruit juice or cider should generally be avoided even if the source is not known because the fruit may have come in contact with contaminated animal feces in the orchard.
    
  • Use caution when traveling, especially to foreign countries. Do not eat foods from street vendors. Don't drink water or drinks with ice cubes made from tap water if the country is deemed unsafe. Check the Travelers' Health Web site of the Centers for Disease Control and Prevention for travel information for your destination.

  Diarrhea Prognosis

  Symptoms should begin to improve two to three days after the original diarrheal episode. Loose stools may persist longer than other symptoms.

  Serious disease is usually seen in individuals who become severely dehydrated, particularly infants, the elderly, or other people with significant medical illnesses.