Understanding Cystic Fibrosis

Physiologic Consequences

Symptoms

Thick, sticky mucus causes most of the symptoms of CF. The most common symptoms of CF include:⁴

Persistent cough, often with phlegm
Frequent lung infections
Wheezing or shortness of breath
Very salty-tasting skin
Poor growth or weight gain despite a good appetite
Greasy, bulky, foul-smelling stools
Stomach pain and discomfort caused by too much gas in the intestines
Dehydration

Systemic Impact

Impact of the Respiratory System^1,4

Mucus build-up in the lungs makes it easy for bacteria to grow and leads to repeated, serious lung infections.

Over time, the infections can cause serious lung damage and a progressive decline in lung function. Complications related to lung infections, including respiratory failure, are the leading cause of death in patients with CF.

Many patients require hospitalization for treatment of these lung infections.

Impact on the Digestive System^1,4

The thick, sticky mucus CF produces can block ducts, or tubes, in the pancreas. As a result, digestive enzymes produced by the pancreas cannot reach the small intestine. Without pancreatic enzymes, the intestines cannot fully absorb fats and proteins from digested food, which causes:

Nutrients to leave the body unused, so patients with CF frequently become malnourished.
A deficiency in the fat-soluble vitamins A, D, E, and K.
Stools to become bulky, often leading to painful intestinal gas or bloating; severe cases can result in blockage called distal intestinal obstruction syndrome

Impact on Sweat Glands¹

The abnormal gene prevents patients with CF from absorbing salt (sodium chloride, or NaCI) from sweat as it moves through the sweat ducts. When people with CF perspire, their bodies lose large amounts of salt, making their skin taste salty.

References:
1. Boucher RC. Cystic Fibrosis. In: Kasper DL, Braunwald E, Fauci AS, Hauser SL, Longo DL, Jameson JL et al., editors. Harrison's Internal Medicine. 16th ed. New York: McGraw-Hill; 2005. p. 1-9.
4. National Heart Lung and Blood Institute. What Is Cystic Fibrosis. US Department of Health and Human Services National institute of Health 2005;1.

Understanding