Cystic Fibrosis / Digestion (Pediatric)

What is cystic fibrosis?

CF is caused by a fault in a certain gene known as the cystic fibrosis transmembrane conductance regulator (CFTR). This gene makes a protein that controls the movement of salt and water to and from the body’s cells.


In CF, the gene does not work properly. As a result, the body produces abnormally thick and sticky mucus and very salty sweat.

This thick sticky mucus clogs up the lungs leading to lung infection and breathing difficulties. It can also clog the ducts of pancreas preventing digestive enzymes from reaching the intestine where they are needed to break down food for absorption. This leads to nutritional deficiencies.

Thickened secretions may also cause liver problems in patients with CF. Bile secreted by the liver to aid in digestion may not drain adequately. Over time, this can lead to scarring of the liver.

What are the symptoms of cystic fibrosis?

  • Malnutrition
  • Abdominal pain
  • Constipation
  • Failure to thrive
  • Abnormal stools (greasy and bulky)
  • Intestinal obstruction
  • Persistent respiratory symptoms (difficulty breathing, constant cough with thick mucus)

Nearly 85% of patients with CF cannot produce the enzymes needed to digest and absorb fats, proteins and starch (referred to as pancreatic insufficiency). The failure to digest (maldigestion) and absorb food, nutrients and vitamins (malabsorption) leads to poor outcomes associated in patients with CF. Symptoms of maldigestion/malabsorption include:

  • Poor weight gain despite a good appetite
  • Abdominal pain, gas, bloating
  • Frequent loose, foul smelling stools

The main nutritional problems for child with CF include:

  • Poor growth or poor weight gain
  • Vitamin deficiencies, especially the fat soluble vitamins A, D, E, K
  • Poor bone health – due to malabsorption of Vitamin D and calcium (this increases ones risk for broken bones and osteoporosis later in life)
  • Cystic Fibrosis Related Diabetes (CFRD)
  • Increased salt loss
  • Essential fatty acid deficiency

How is cystic fibrosis treated?

Our experts will also closely monitor your child and make the necessary recommendations for optimal outcome at every visit.

Patients with CF also require more calories than other patients secondary to increased energy demands due to coughing, increased work of breathing, etc.

They also need help to digest and absorb their food better. Nutrition will be critical part of your child’s treatment, throughout his or her life.

Most CF patients take pancreatic enzyme replacements. These help patients with pancreatic insufficiency digest and absorb their food better.

Your pediatric gastroenterologist and dedicated nutritionist will find the right enzyme and dosage. These enzymes will improve absorption of food and nutrients and help you gain weight. They may improve liver function in young patients who have associated liver disease.