By: Dr. MARIA ALICE
Consultant in General and Family Medicine
Director – Luzdoc, International Medical Service
IT IS not easy to understand what diarrhoea is, as it is not one disease, but a symptom of many diseases and resulting from many causes. Most people think of diarrhoea as an illness during which they have more frequent, loose, watery stools.
Almost everyone has diarrhoea at some point in life. Intestinal infections can spread anywhere, from campgrounds to luxury cruise ships, all over the world, affecting people of every age, race and background.
In developing countries, where illnesses that cause diarrhoea are more common and where healthcare is less readily available, diarrhoea is a major health concern because of its potential to cause severe, life-threatening dehydration, especially in the elderly and in infants, being a leading cause of death in children. That is because children’s immune systems are not mature until about age six, and adult immune systems tend to become less efficient later in life.
Normally, the food remains in liquid form during most of the digestive process. When the unabsorbed food residue passes through the large intestine (colon), most of the fluids are absorbed and what remains is a semisolid stool.
In diarrhoea, the food and fluids you ingest pass too quickly or in too large an amount, or both, through your colon. The fluids are not sufficiently absorbed and the result is a watery bowel movement. In addition, the lining of the colon may be inflamed or diseased, making it less able to absorb fluids.
Causes of diarrhoea
Infectious – Many different things can cause diarrhoea but one is most likely to come down with it after coming into contact with infectious organisms and agents like a virus, a bacteria or a parasite.
Food poisoning can occur when a person eats or drinks food contaminated with certain types of bacteria, viruses, or parasites. Food can be contaminated during growing, processing and handling, or through dirt, dust and water found in the environment.
Food poisoning causes symptoms of nausea, vomiting, abdominal cramps and diarrhoea. The time it takes for symptoms to appear, how severe the symptoms are and how long the symptoms last, depends on the infecting organism and the age and overall health of the person infected.
The very young and the very old may be most affected by food poisoning. Their symptoms may last longer, and even the types of food poisoning that are typically mild can be life-threatening. This may also be true for pregnant women and people with impaired immune systems, such as those with long-lasting (chronic) illnesses.
The symptoms of food poisoning are often caused by chemicals (toxins) released by the infecting bacteria. Food poisoning may spread if a person comes into contact with stool from an infected person. To guard against diarrhoea caused by contaminated food, use dairy products that have been pasteurized and serve food right away or refrigerate it after it has been cooked or reheated. Leaving food out at room temperature can encourage growth of bacteria.
Defrost food safely; do not thaw foods at room temperature. The safest way to thaw foods is to defrost foods in the refrigerator or to microwave the food using the “defrost” or “50 per cent power” setting. Running cold water over the food also safely thaws the food.
Many people who travel to developing countries contract what is called “traveler’s diarrhoea,” usually after drinking contaminated water.
Non-infectious – A number of medical conditions may cause diarrhoea, like inability to digest certain foods, a shortened intestine as a result of surgery, thyroid disease, diabetes, inflammatory bowel disease such as ulcerative colitis or Crohn’s disease and irritable bowel syndrome.
Medications and other substances – Many medications can cause diarrhoea, particularly antibiotics that destroy both good and bad bacteria, which can disturb the natural balance of bacteria in the intestines.
When to seek medical advice
See a doctor if diarrhoea persists for more than two days in adults, one day in children younger than four years old, eight hours in babies three to six months old and four hours in infants younger than three months of age.
Do not even wait any time at all if there is stomach pain that is not relieved by passing gas or stools, evidence of dehydration with excessive thirst, dry mouth or skin, little or no urination, severe weakness, dizziness or light-headedness, dark-coloured urine, if there is severe abdominal or rectal pain, bloody or black stools, or a fever.
The doctor may suggest blood or stool tests to check for signs of infection or other abnormalities and will advise how to replace the fluids and salts lost during diarrhoea. A stool culture may be done if there is suspiction that contaminated food was ingested, if symptoms are severe, or the diagnosis is uncertain. Blood tests, including a complete blood count and a chemistry screen, can help indicate whether the patient is severely ill or dehydrated and to help determine whether the cause is a virus or a bacteria, or even to rule out other causes.
The body needs adequate levels of salts and electrolytes (minerals such as sodium and potassium) in order to maintain the electric currents that keep the heart beating. Disruption of the body’s fluid and mineral levels creates an electrolyte imbalance that can be serious, unless restored by replacing fluids and salts either through an intravenous infusion or by drinking an electrolyte mixture, if the person tolerates it.
People with long-lasting (chronic) conditions, such as diabetics, are more likely to have severe dehydration and should be watched closely for symptoms, especially when there is associated vomiting.
Encouraging children to wash their hands can help prevent the spread of viral diarrhoea and, because viral diarrhoea spreads easily, it is better to keep children home from school if they have it.
Over-the-counter anti-diarrhoea medications may slow diarrhoea, but they will not speed recovery. Certain infections may be made worse by these medications because they prevent the body from getting rid of what is causing the diarrhoea. Also, these drugs are not always safe for children. Check with your doctor before using these medications.
One last note: calling it “the runs” is a very appropriate name, as when it hits strong and hard, you will be running to a certain compartment of the house! And it better be near…
Best health wishes,
Dr. Maria Alice
