What is cystic fibrosis?
Cystic fibrosis (CF) is a genetic disorder that affects the lungs, digestive system and other organs in the body. CF disrupts the normal function of epithelial cells, cells that line passageways in the respiratory tract, digestive system, sweat glands and reproductive system. In people with CF, a faulty gene prevents epithelial cells from being able to regulate the way salt passes across cell membranes. This disrupts the essential balance of salt and water needed to maintain a healthy, thin coating of fluid and mucus inside the lungs, pancreas, liver and other organs.
CF affects the body in many ways. In the lungs, thick, sticky mucus clogs the airways and traps germs, like bacteria, leading to lung infections, inflammation and airway damage. In the pancreas, the buildup of mucus prevents the release of digestive enzymes that help the body absorb fats, proteins and other key nutrients. Children with CF can have problems gaining weight, even with a normal diet and a good appetite. In the liver, the thick mucus can block the bile ducts, causing liver disease.
What causes cystic fibrosis?
CF is a genetic disease, meaning that it is caused by a faulty CF gene. In people with CF, mutations in the gene that produces the cystic fibrosis transmembrane conductance regulator (CFTR) protein leads to a CFTR protein that doesn’t work properly or an inadequate amount of functional CFTR protein. CFTR protein helps to maintain the balance of salt and water needed for a healthy, thin coating of fluid and mucus inside the body.
Who gets cystic fibrosis?
CF is an inherited disease meaning that it is passed down from parents. People with CF inherit two copies of the abnormal or mutated CF gene, one copy from each parent. Both parents must have at least one copy of the abnormal gene (i.e. they are ‘carriers’ of the mutated gene). There are more than 1,700 known mutations of this gene that can cause CF. The most common mutation in the CF gene is called F508del. Over 80% of people with CF in the U.S. have at least one copy of the F508del mutation.
Caucasians have the highest inherited risk for CF and Asian Americans have the lowest. In the U.S. today, about 1 in 3,000 to 4,000 Caucasian children and 1 in 8,000 to 9,000 Hispanic children are born with CF. This compares with about 1 in 17,000 African Americans and 1 in 31,000 Asian Americans.
Although the chances of inherited risk may vary, CF has been identified in every geographic area of the world, among every ethnic population. More than 30,000 people are living with CF in the U.S. (more than 70,000 worldwide).
What are the signs and symptoms of cystic fibrosis?
The most common symptoms of CF among infants and children include:
- Lack of weight gain or failure to thrive
- Frequent greasy or bulky stools
- Excessive intestinal gas
- Difficulty with bowel movements or constipation
- Abdominal pain or discomfort
- Salt crystals or salty taste on skin
- Nasal congestion
- Sinus problems
- Asthma-like symptoms
- Chronic cough that produces thick, discolored mucus
- Frequent lung infections including pneumonia and bronchitis
- Shortness of breath, even while resting
Some children with CF begin having symptoms shortly after birth. All newborns have meconium, which is the thick, dark, putty-like substance that is a baby's first stool. About 10 to 15% of people with CF are born with a condition called meconium ileus, in which thick meconium blocks part of the small intestine called the ileum, leading to a bowel obstruction (blockage).
What tests are used to diagnose cystic fibrosis?
CF is most commonly diagnosed as part of newborn screening. The two most definitive tests for diagnosing CF are a sweat chloride test and a genetic test for CF-causing gene mutations.
- Newborn screening: This screening test occurs shortly after birth when a few drops of blood from a heel prick are used to test for certain health conditions, including CF. All 50 U.S. states screen newborns for CF, but the method for screening differs from state to state. Every state's CF newborn screening program begins with a blood test from the baby to check the levels of a chemical made by the pancreas called immunoreactive trypsinogen (IRT). An abnormal newborn screen means the baby may have CF and that further testing, including a sweat test, is required in order to rule out or diagnose CF.
- Sweat chloride test: In the sweat test, a small, non-painful, electric current is used to carry a chemical called pilocarpine into the skin of the forearm. This stimulates sweat glands in the area to produce sweat, which is collected in a small tube and the salt (chloride) content is measured. A diagnosis of CF is made if the sweat chloride concentration is greater than 60 mmol/L.
- Genetic test: We also diagnose CF by identifying two CF mutations on genetic testing. This testing is most often performed by looking at a child’s DNA in a blood sample.
Several other tests are standard parts of routine care that we use to treat a child with CF:
- Chest X-rays or chest CT scans to monitor for structural lung injury and signs of lung infection
- Blood tests to evaluate vitamin levels, electrolyte (salt) levels, kidney and liver function tests
- Respiratory (sputum) cultures test for Pseudomonas aeruginosa, Staphylococcus aureus, Haemophilus influenzae and other bacteria and microbes in the lungs
- Pulmonary function tests to measure the effects of CF on breathing for children who are old enough to cooperate with testing
How is cystic fibrosis treated?
CF symptoms can differ widely from person to person. While treatment plans often contain many of the same elements, they are tailored to each child’s unique circumstances.
The main treatment strategies for people with CF include:
- Airway clearance helps loosen and get rid of the thick mucus that can build up in the lungs.
- Inhaled medicines open the airways or thin the mucus. These are liquid medicines that are made into a mist or aerosol and inhaled through a nebulizer that include antibiotics to fight lung infections and therapies to help keep the airways clear.
- Pancreatic enzyme supplement capsules improve the absorption of vital nutrients. These supplements are taken with every meal and most snacks. People with CF also usually take CF-specific multivitamins.
- CFTR modulators target the underlying defect in the CFTR protein. Because different mutations cause different defects in the protein, the medications that have been developed are only effective in people with specific mutations.
The CF Foundation recommends that all people with CF be followed in an accredited CF care center with regular visits at least every three months and more often during the first year of life.
Why choose us for your child’s cystic fibrosis treatment?
Children's Colorado is the site of one of the premiere CF clinical care and research centers in the country. The Mike McMorris Cystic Fibrosis Research and Care Center at Children's Colorado delivers state-of-the-art care to people with CF, advances the field of CF and helps in the development of better treatments for people with CF through cutting-edge research and clinical trials and provides education for healthcare professionals and families with CF.
Our center, accredited by the Cystic Fibrosis Foundation, is the largest pediatric CF clinical care center in the U.S. Our pediatric program cares for almost 400 children and adolescents with CF throughout the Rocky Mountain region. Our program has satellite and outreach clinics throughout the state of Colorado. We also serve as a national referral center for patients with difficult-to-treat infections because of our experience and advanced diagnostic capabilities.
Our program consistently strives to offer the highest quality care for children with CF and is dedicated to providing patient-focused treatment and support for families:
- We have established a CF Family Advisory Council, made up of our patients' parents and clinical staff, who work as partners with the CF clinical care team to ensure excellence in the development and delivery of medical care for those with CF and their families in the Rocky Mountain region.
- Our multidisciplinary CF care team includes board-certified pediatric pulmonologists and gastroenterologists, pediatric endocrinologists, pediatric psychologists, CF clinical nurse specialists, registered dietitians, social workers, respiratory therapists, physical therapists, a CF pharmacist, research coordinators, as well as administrative support staff.
- Our clinics see children with CF five days a week, Monday through Friday.
- We offer comprehensive inpatient and outpatient multidisciplinary medical care.
- Our program consistently ranks as one of the top performing CF centers in the country based on lung function data in our children and adolescents.
- We work to continually improve care at our CF center through quality improvement initiatives and educational programs for healthcare providers and families.
- Our Center is one of the original members of the CF Foundation Therapeutics Development Network, which conducts the early human clinical trials of potential treatments in CF. We consistently rank among the top enrolling centers for clinical trials in the country, which is a tribute to our families and our CF research staff.
- Children's Colorado serves as a national referral and reference laboratory for sweat collection, sputum collection and inflammatory mediator analysis (measurement of proteins that contribute to lung inflammation and injury) and for microbiome analysis (examining microbial communities in the lungs of people with CF).
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Children's Colorado in the news
Colorado Public Radio
November 6, 2019
The newly approved triple-combo drug, Trikafta, has the potential to help 90% of people living with CF and add years to life expectancy.