Cystic fibrosis is a progressive genetic disease caused by mutations, or changes, in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. Cystic fibrosis is most common in people of Northern European ancestry, but it occurs in people of all races and ethnicities.
People who inherit a mutated CFTR gene from both of their parents are born with cystic fibrosis, while people who inherit a mutated CFTR gene from only one parent are cystic fibrosis carriers. Cystic fibrosis is typically diagnosed at birth using genetic screening or by age two when a health care provider notices cystic fibrosis symptoms. These can include consistently coughing up mucus, getting a lot of colds and sinus infections, and wheezing. A test—such as genetic testing and a sweat test that measures the amount of chloride in your sweat—will be done to confirm the diagnosis.
The CFTR gene provides instructions for the CFTR protein, which acts as a channel for chloride to promote water and salt secretion in different organs. The movement of water and salt is necessary to produce mucus, a gel-like material that protects and lubricates the lining of the airways, the intestines and other organs.
In cystic fibrosis, however, CFTR can’t move chloride, which reduces fluid production and causes mucus to become thick and sticky. In the lungs, mucus blocks the smaller airways and traps bacteria, causing recurring infections and inflammation. In the digestive system, thick mucus blocks the release of digestive enzymes from the pancreas, preventing the absorption of nutrients, calories and vitamins from food. People with cystic fibrosis often experience malnutrition and poor growth.
Currently, there is no cure for cystic fibrosis. However, advances in medicine have allowed people living with cystic fibrosis to manage their symptoms and live longer, more fulfilling lives. Oral and inhaled antibiotics are used to treat lung infections. Physical therapy and mucus-thinning medications keep the airways clear. Oral pancreatic enzymes, stomach acid-suppressing medications and a high-calorie, nutritious diet help promote digestion and combat malnutrition.
Recently developed CFTR modulator drugs can help the abnormal CFTR protein work properly in people with specific types of CFTR mutations. These treatments, along with recommendations for regular physical activity and a healthy lifestyle, help preserve long-term lung function.
Cystic fibrosis is a lifelong condition. Because there are many types of cystic fibrosis-causing mutations, the specific symptoms and their severity can vary from person to person. Treatment plans focus on each person’s specific needs and may change over time as the disease progresses.
Rowena Woode, DVM, PhD, is a postdoctoral research scientist at the University of Missouri-Columbia. Her research explores how cystic fibrosis affects the digestive system. Woode is interested in studying how cystic fibrosis-causing mutations disrupt the intestinal barrier and increase gastrointestinal cancer risk.