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This information was reviewed and approved by Sara Brayshaw, RN, MSN (10/1/2019).

Question: How does cystic fibrosis affect the body?

Answer: Cystic fibrosis (CF) leads to the secretion of unusually thick, dehydrated, and sticky mucus in many tissues of the body, including the airways, pancreatic ducts, sweat ducts, sinuses, and bowels. Obstruction of the pancreatic ducts severely damages the pancreas, and reduces the body's ability to make the enzymes required to digest proteins and fat. Obstruction of the small airways of the lung results in the permanent dilation of these bronchi (bronchiectasis), and provides a site where certain infections can take hold. The thick and dehydrated mucus prevents the normal clearance of bacteria and other microbes from the lungs, and patients acquire chronic infections.


Question: Which genes cause CF?

Answer: CF is a genetic disease caused by a mutation in a gene named the cystic fibrosis transmembrane conductance regulator (CFTR). There are approximately 1500 different CFTR mutations which can cause CF. The most common mutation is named ΔF508, and approximately two-thirds of all CFTR mutations worldwide are ΔF508. While having 2 copies (homozygote) of ΔF508 is associated with severe disease, many of the less common mutations are associated with less severe clinical symptoms.


Question: How is cystic fibrosis inherited?

Answer: The inheritance pattern is autosomal recessive. This means that in order to have symptoms of cystic fibrosis, an individual must have two defective CFTR genes, by inheriting a copy of the CFTR gene from both mother and father.


Question: Is there a way to tell if someone is a carrier of the CF gene?

Answer: People with a single CFTR mutation are termed carriers, and do not have symptoms of CF. Historically, it was determined someone was a carrier is if their child had cystic fibrosis. Now, genetic testing can reveal if someone is a carrier.

Question: What are cystic fibrosis's most frequent symptoms?

Answer: The most common symptoms of cystic fibrosis include:

  • Obstruction of the bowel at birth
  • Frequent greasy, bulky stools, or difficulty in bowel movements
  • Very salty-tasting skin
  • Persistent coughing, at times productive with sputum
  • Frequent respiratory infections
  • Wheezing or shortness of breath
  • Poor growth and difficulty with weight gain
  • Chronic sinusitis, sinus infections, and nasal polyps
  • Clubbing of the fingers and toes 
  • Male infertility with an absence of sperm
  • Malnutrition and vitamin deficiency


Question: Does CF affect other major organs of the body besides the lungs?

Answer: Yes; one of the most commonly affected is the pancreas. Nearly 90% of people with CF lack the ability to produce sufficient enzymes from the pancreas that help with digestion.This condition greatly reduces the capacity to metabolize and absorb dietary fats and proteins. Carbohydrate absorption can also be impaired. Symptoms include greasy and foul-smelling diarrhea, abdominal pain, failure to gain weight, and malnutrition.


Question: How early can cystic fibrosis be diagnosed?

Answer: Patients with CF are typically diagnosed in infancy due to symptoms of diarrhea and malnutrition.


Question: What's the life expectancy for someone with CF?

Answer: Historically, children with cystic fibrosis died as infants, and as recently as 1980 the median survival was less than 20 years. However, over the past 3 decades the lifespan of CF patients has risen dramatically, and in 2006 the median survival in the United States was 37.5 years.  


Question: Is physical exercise capable for someone with cystic fibrosis? Is it helpful or harmful?

Answer: Nearly always, aerobic exercise is helpful to patients with CF as an addition to other forms of airway clearance, loosening and getting rid of the mucus from the lungs.

Question: What is the future of CF?

Answer: Improving therapies, combined with the availability of better diagnostic testing, has resulted in a steady increase in the average age of cystic fibrosis patients. Very soon, CF will be primarily a disease of adulthood, and increasingly patients with cystic fibrosis are surviving past middle age. While much attention has been focused on the process of adolescents with CF transitioning from the pediatric setting to adult programs within Care Centers, a similar process of transition will need to occur within the medical community, as increasingly adult physicians will be required to provide the majority of cystic fibrosis care. Older men and women with CF have unique healthcare needs, with complex infections, malignancies, and unique forms of diabetes and osteoporosis. Thus, the need for CF Centers with experience and commitment to adult care will continue to grow.


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