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How does cystic fibrosis affect the lungs and digestive system?

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Medical illustration of the human chest showing the lungs, diaphragm, ribs, trachea, bronchus, and bronchioles, with one lung cut away to reveal internal structures. — respiratory disease The bronchioles of the lungs are the site where oxygen is exchanged for carbon dioxide during the process of respiration. Inflammation, infection, or obstruction of the bronchioles is often associated with acute or chronic respiratory disease, including bronchiectasis, pneumonia, and lung abscesses.

Cystic fibrosis is an inherited disorder caused by mutations in the CFTR gene, which disrupts the transport of chloride and water across cell membranes. This leads to the production of abnormally thick, sticky mucus that affects the exocrine glands in the respiratory and digestive systems.12

Impact on the Lungs

In the lungs, this thick mucus accumulates and plugs the bronchi, which obstructs airways and makes breathing difficult. This environment promotes chronic respiratory infections, often caused by bacteria such as Staphylococcus aureus or Pseudomonas aeruginosa. Over time, patients experience recurrent pneumonia, chronic cough, and progressive loss of lung function, which is the leading cause of mortality in individuals with the disease.2

Impact on the Digestive System

In the digestive tract, thick secretions block the ducts of the pancreas, preventing essential digestive enzymes from reaching the intestines. This results in maldigestion and malabsorption of nutrients, often leading to malnutrition despite an adequate diet. Additionally, similar plugging processes can cause scarring in the hepatic biliary system, potentially leading to cirrhosis.23