Irritable bowel syndrome (IBS)

What is irritable bowel syndrome?

Irritable bowel syndrome is one of the manifestations of functional abdominal pain. Functional means that there is no organic disease. Functional abdominal pain describes a constellation of symptoms as a result of intestinal motility disorders. Symptoms may include:

  • Flatulence.
  • Bloating.
  • Diarrhea.
  • Constipation.
  • Urgency with defecation.
  • Incomplete sensation of defecation.
  • Passage of mucus in the stool.

What causes irritable bowel syndrome?

The digestion and propulsion of nutrients and fluids through the gastrointestinal system (GI) is a very complicated and very well organized process. The GI tract has its own muscles and nerves that connect, like an electrical circuit, to the spinal cord and brain. Neuromuscular events occurring in the GI tract are relayed to the brain through neural connections, and the response of the brain is also relayed back to the gastrointestinal tract. As a result of this activity, motility (the ability to move spontaneously)  and sensation in the bowel is generated. An abnormality in this process results in a disordered propulsion of the intestinal contents and generates the sensation of pain.

The nerves that control the digestive tract may also be more sensitive to the activity associated to the process of digestion. Children with irritable bowel syndrome may be more aware of gas and motion and rumbles of the intestines. They are more aware of these discomforts and hence more irritated when they occur. The child who experiences the symptoms of irritable bowel syndrome is thought to be as a result of the following and their interaction:

  • Motility abnormalities.
  • Visceral hypersensitivity - The viscera are the organs inside the abdominal cavity. The GI tract is the largest in the abdomen and it has been seen that in patients with functional GI disorders there is heightened sensitivity to changes within the intestine, whether to the presence of food or as a result of distension of the viscera.
  • Psychosocial problems - It is well known that the emotional state of the person can directly influence the activity in the gastrointestinal tract. High levels of anxiety, stress or anger can induce diarrhea.
    A stressful event is not limited to emotional issues but also includes physical stresses such as a viral illness or any other particular disease state.

All of the above factors can trigger the occurrence of symptoms. It is important to stress to the child with a functional bowel disorder that abdominal pain is real and not imaginary.

Who is affected by irritable bowel syndrome?

  • Irritable bowel syndrome occurs in both children and adults.
  • Ten to 15 percent of school-aged children and adolescents have symptoms of functional abdominal pain to the point of interrupting their daily normal life.
  • Thirty-three percent of adults who have irritable bowel syndrome can trace their symptoms back to childhood.
  • Girls are affected by the disorder slightly more often than boys.
  • There is no known gene that causes irritable bowel syndrome, but the disorder does seem to occur more often in families where either a child or a parent has the disorder.

Why is irritable bowel syndrome a concern?

Children with irritable bowel syndrome often do not feel well. Those who have diarrhea may have little warning of their need to go to the bathroom, and, therefore, may be embarrassed and avoid going to school or socializing with their schoolmates. Children can become depressed or anxious because of the disorder.

Most children with irritable bowel syndrome continue to grow and develop normally. However, some children may eat less to avoid the pain that can accompany digestion, and therefore, lose weight.

Its greatest risk in sickness resides in the fact that it affects normal daily activity of the child, affecting school and peer relations.

What are the symptoms of irritable bowel syndrome?

According to the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), irritable bowel syndrome in children tends to produce two types of symptoms: diarrhea or pain, depending on the age of the child. Symptoms may include:

  • Recurrent abdominal pain. The pain becomes chronic when it has been present for a period greater than three months.
    An altered bowel pattern with diarrhea and constipation, all of which suggests intestinal motility dysfunction.
  • Headaches.
  • Pallor.
  • Nausea.
  • Dizziness.
  • Anorexia.
  • Limb pain.

In children, symptoms of functional bowel disorders are variable and are age dependent. For example:

  • Infantile colic (younger than 4 months of age).
  • Gastroesophageal reflux (younger than 2 years of age and then reappears in adolescence and adulthood).
  • Chronic non-specific diarrhea (younger than 4 years of age).
  • Constipation (any age).
  • Irritable bowel syndrome (adolescents and adults).

The symptoms of irritable bowel syndrome are not unique for the condition. Altered bowel pattern and abdominal pain could be symptoms of organic disease - one reason why you should always consult your child's physician for a diagnostic work-up.

How is irritable bowel syndrome diagnosed?

Your child's physician will obtain a thorough medical history, perform a full physical examination and obtain screening laboratories to assess for infection and inflammation. The laboratory tests, imaging studies and procedures to be performed will be dictated by the history and physical examination. Tests and procedures that your child's physician may order may include the following:

  • Blood tests - to evaluate whether your child is anemic, has an infection, or has an illness caused by inflammation or irritation.
  • Urine analysis and culture - to help assess for urinary tract infections.
  • Stool sample - for culture to check for bacteria and parasites that may cause diarrhea.
  • Stool samples for occult blood - occult blood cannot be seen and is only detected by a special solution that turns blue when coming into contact with blood. It suggests an inflammatory source in the gastrointestinal tract.
  • Lactose breath hydrogen test - to determine if your child is intolerant to lactose, a sugar present in milk and milk products.
  • Abdominal x-ray - a simple study that will give the physician an idea of how the internal organs look.
  • Abdominal ultrasound - a diagnostic imaging technique which creates images from the rebound of high frequency sound waves in the internal organs.
  • Endoscopy - a test that uses a small, flexible tube with a light and a camera lens at the end (endoscope) to examine the inside of part of the digestive tract. Tissue samples from inside the digestive tract may also be taken for examination and testing.

Rarely, the physician will require ultrasound and an endoscopy.


diagnostic procedures 4

diagnostic procedures 5

  • Colonoscopy - a test that uses a long, flexible tube with a light and camera lens at the end (colonoscope) to examine inside the large intestine.



Treatment for irritable bowel syndrome:

Specific treatment of irritable bowel syndrome will be determined by your child's physician based on:

  • Your child's age, overall health and medical history.
  • Extent of the problem.
  • Your child's tolerance for specific medications, procedures or therapies.
  • Expectations for the course of the condition.
  • Your opinion and preference.

The main objective of treatment for irritable bowel syndrome to restore normal daily function. Management begins with the positive diagnosis of irritable bowel syndrome. This will give your child reassurance that the child does not have any life-threatening condition.

Environmental modification is important to identify the stresses surrounding your child and reverse them. Parents and school teachers must support the child rather than concentrating on the pain. Try to help the child focus on something fun or pleasant during a painful episode.

In lactose intolerant patients, restriction of lactose or supplementing the enzyme that digests the sugar (lactase/Lactaid®) is recommended since this sugar can be a trigger for symptoms of irritable bowel syndrome.

A controversial issue is the use of high fiber in children since it could promote flatulence and abdominal distension. It is recommended in the adult population and it may be beneficial in children in which the symptom of constipation predominates.

Depending on the severity of the symptom, medication may be indicated. In rare cases, pain control needs to be administered by specialists in the field of pain management. Biofeedback has become part of the treatment strategy, as well as acupuncture.

How much fiber is enough?

For children two years of age and older, use the following guideline: The child's age plus five equals the number of grams of fiber that should be eaten daily.

For example, a 4 year old needs four + five grams per day = nine grams of fiber per day.

What foods are high in fiber?

Fiber is found in foods such as:

  • Fruits.
  • Vegetables.
  • Whole wheat breads and cereals.
  • Beans.
  • Peas.

Suggestions for increasing fiber intake:

  • Use raw vegetables and fruits with dip.
  • Use unpeeled potatoes for potato salad or french fries.
  • Add high-fiber cereal or fruit to ice cream, frozen yogurt or yogurt.
  • Add beans to soups, stews, and salads.
  • Use whole wheat bread for sandwiches.

What are good fiber sources?

BREAD Whole wheat bread, granola bread, wheat bran muffins, Nutri-Grain® waffles, popcorn
CEREAL Bran Flakes®, Raisin Bran®, Shredded Wheat®, Frosted Mini Wheats®, oatmeal, Muslix®, granola, oat bran All-Bran®, Bran Buds®, Corn Bran®, Fiber One®, 100% Bran®
VEGETABLES Beets, broccoli, brussel sprouts, cabbage, carrots, corn, green beans, green peas, acorn and butternut squash, spinach, potato with skin, avocado
FRUITS Apples with peel, dates, papayas, mangos, nectarines, oranges, pears, kiwis, strawberries, applesauce, raspberries, blackberries, raisins Cooked prunes, dried figs
MEAT SUBSTITUTES Peanut butter, nuts Baked beans, black-eyed peas, garbanzo beans, lima beans, pinto beans, kidney beans, chili with beans, trail mix

High-fiber meal vs. a typical meal:

Typical Meal

High-Fiber Meal

Cornflakes ½ cup
Donut 1
Milk ½ cup
Orange juice ½ cup

Total grams of fiber = 0.5 grams

Raisin bran ½ cup
Bran muffin
Milk ½ cup
Orange juice ½ cup

Total grams of fiber = 5 grams

Beef patty 3 ounces
Hamburger bun
French fries
Green beans ½ cup
Canned pears ½ cup
Milk 1 cup

Total grams of fiber = 5 grams

Beef patty 3 ounces
Whole wheat bun
Baked potato with skin
Baked beans ½ cup
Pear with skin
Milk 1 cup

Total grams of fiber = 15 grams

Grilled chicken 3 ounces
Lettuce salad
White rice ½ cup
Watermelon ½ cup
Milk ½ cup

Total grams of fiber = 1.5 grams

Grilled chicken 3 ounces
Broccoli ½ cup
Brown rice ½ cup
Strawberries ½ cup
Milk ½ cup

Total grams of fiber = 6 grams