Cystic fibrosis causes problems with how the lungs function
The CFTR* protein is found throughout the body, meaning that people with cystic fibrosis (CF) may experience a wide range of symptoms.
Inside the lungs is a network of tubes that divide into smaller and smaller tubes as you go deeper into the lungs. These tubes are called airways. The airways are lined with cilia, small hairs that sway back and forth to sweep mucus out of the airways.
Airway of a person without CF
Normally, mucus in the lungs traps germs that can cause an infection. Then, the mucus is swept out of the lungs by the cilia. This mucus is coughed up and the germs are expelled.
For cilia to be able to do this the inside of the airways needs to be moist. This allows the cilia to move back and forth freely.
*CFTR = Cystic fibrosis transmembrane conductance regulator
Airway of a person with CF
People with CF have reduced numbers of CFTR proteins or faulty CFTR proteins, which may result in the production of thick mucus.
- Shortness of breath.
- A persistent cough that produces thick phlegm (sputum).
- Lung infections (from bacteria such as Pseudomonas aeruginosa, Burkholderia cepacia and Staphylococcus aureus).
6(damage to the airways that causes them to become wider and makes it harder to move air in and out as a person breathes and harder to clear mucus).
The build up can lead to
Airway of person without and with CF
Mucus is swept out of the lungs by cilia
Cilia are unable to sway freely and sweep mucus from the lungs
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