Health Information

Cystic Fibrosis and the Respiratory System

How does cystic fibrosis affect the respiratory system?

Cystic fibrosis (CF) is an inherited disease marked by an abnormality in the body's salt-, water-, and mucus-making cells. Although CF can't be cured and gets worse over time, improved treatments have helped people with the disease live significantly longer. Most people with CF live into their late 30s, and many into their 50s. Some CF patients now live into their 70s. 

CF causes thick mucus to build up and clog certain parts of the body like the lung. The buildup is caused by an abnormal gene. called the cystic fibrosis transmembrane regulator (CFTR). CFTR controls the flow of water and  salt in and out of the body's cells. Changes cause mucus to become thickened and sticky. This first affects the  small airways in the lungs, but eventually it can affect all airways.

Children with CF may develop lung infections, because bacteria that are normally cleared from the lungs remain in the thickened mucus. Many of these lung infections are chronic. The most common bacteria that cause lung infections in people with CF is Pseudomonas aeruginosa.



  • Chronic cough

  • Coughing up blood

  • Collapsed lung

  • Clubbing, The rounding and enlargement of the fingers and toes.

  • Heart enlargement

  • Nasal polyps. These are fleshy growths in the nose.

  • Sinusitis. Inflamed nasal sinuses.