Cystic fibrosis (CF) is an inherited genetic disorder caused by changes in the CFTR gene. These changes disrupt the movement of salt and water across cells, leading to thick, sticky mucus that can build up in the lungs, pancreas, and other organs. CF commonly affects breathing and digestion and can also cause complications involving the liver, intestines, sinuses, reproductive system, and other parts of the body. Advances in early diagnosis, specialized care, and treatments that target the CFTR protein have substantially improved health and survival for many people with CF.
Cystic fibrosis occurs in people of all racial and ethnic backgrounds, although it has historically been diagnosed most often in people of European ancestry. According to the Cystic Fibrosis Foundation, close to 40,000 children and adults are living with CF in the United States, while more than 100,000 people have been diagnosed worldwide.
The outlook for people with CF has changed substantially over the past several decades. Earlier diagnosis, specialized multidisciplinary care, improved management of infections and nutrition, and CFTR modulator therapies have helped many people live longer and healthier lives. In the United States, most people living with CF are now adults. Disease severity and treatment options still vary considerably depending on factors such as a person’s CFTR variants, organ involvement, infections, and access to specialized care.
Cystic fibrosis can affect multiple organs because abnormal CFTR protein function disrupts salt and water movement across cell surfaces. The infographic summarizes major effects of CF and common approaches to treatment and management.
Causes
Cystic fibrosis is caused by disease-causing variants in the CFTR gene. This gene provides instructions for making the cystic fibrosis transmembrane conductance regulator (CFTR) protein, which helps regulate the movement of chloride and bicarbonate across cell membranes. When CFTR does not function properly, the balance of salt and water at cell surfaces is disrupted, contributing to thick, sticky secretions in organs such as the lungs and pancreas.
CF is inherited in an autosomal recessive pattern. A person typically develops the condition after inheriting a disease-causing CFTR variant from each parent. When both parents are carriers, each pregnancy has a 25% chance of resulting in a child with CF, a 50% chance of resulting in a child who is a carrier, and a 25% chance of resulting in a child who inherits neither disease-causing variant.
Symptoms
Cystic fibrosis can affect several organs, particularly the lungs, pancreas, intestines, sinuses, liver, and reproductive system. Symptoms vary considerably from person to person depending on age, the organs affected, and the severity of the disease.
In some newborns, the first sign of CF is meconium ileus, an intestinal blockage caused by unusually thick meconium, a baby’s first stool. It can cause abdominal swelling, vomiting, and failure to pass stool. Severe cases can lead to complications such as intestinal perforation and require urgent medical treatment.
Many people with CF also develop pancreatic insufficiency because thick secretions can prevent digestive enzymes from reaching the small intestine. This can interfere with the absorption of fats, proteins, and vitamins and may cause poor weight gain, slowed growth, abdominal symptoms, and bulky, greasy, foul-smelling stools.
Symptoms in Older Children and Adults
Respiratory symptoms can include a persistent or recurrent cough, wheezing, shortness of breath, recurrent lung infections, and chronic sinus problems. As lung disease progresses, some people experience reduced exercise tolerance. More advanced lung disease can be associated with signs such as finger clubbing or low blood oxygen levels.
Digestive symptoms can include constipation, abdominal pain, bloating, and changes in bowel movements. Children may experience difficulty gaining weight or growing as expected, and delayed puberty can occur in some adolescents.
People with CF also lose more salt through their sweat than people without the condition. Their skin may taste unusually salty, and they can be at increased risk of dehydration and salt depletion, particularly during hot weather, exercise, fever, or illness.
Symptoms and their severity vary widely. Some people are diagnosed through newborn screening before symptoms appear, while others with less typical disease may not be diagnosed until later in childhood or adulthood.
Diagnosis
Cystic fibrosis may be identified through newborn screening or diagnosed later when a person develops symptoms suggestive of the condition. A diagnosis is based on a combination of clinical findings and evidence that the CFTR protein is not functioning normally. Sweat chloride testing and genetic testing are among the most important diagnostic tools. Other tests may be used to assess how CF is affecting the lungs, pancreas, liver, and other organs.
Newborn Screening
Newborn screening for cystic fibrosis is performed shortly after birth. In the United States, screening begins with a small blood sample, usually collected from the baby’s heel, that measures immunoreactive trypsinogen (IRT), a substance produced by the pancreas.
Babies with CF often have elevated IRT levels, but a high IRT result does not by itself diagnose cystic fibrosis because IRT can also be elevated for other reasons. Screening protocols vary and may combine IRT measurement with testing for CFTR gene variants. Babies with a positive newborn screen are referred for further evaluation, which usually includes a diagnostic sweat chloride test.
Newborn screening allows many children with CF to begin specialized care before significant symptoms develop. However, screening does not identify every person with the condition, and some people with less typical forms of CF may be diagnosed later in childhood or adulthood.
Genetic Testing
Genetic testing looks for disease-causing variants in the CFTR gene. Identifying two CF-causing variants, together with appropriate clinical or laboratory findings, can help establish a diagnosis of cystic fibrosis.
Genetic testing can also be useful when sweat test results are inconclusive or when a person’s symptoms suggest CF despite an uncertain initial evaluation. Because many different CFTR variants have been identified, more extensive genetic analysis may sometimes be needed when standard testing does not provide a clear answer.
Sweat Test
The sweat chloride test is the standard diagnostic test for cystic fibrosis. It measures the concentration of chloride, a component of salt, in sweat.
During the test, a medication called pilocarpine and mild electrical stimulation are used to encourage a small area of skin to produce sweat. The sweat is collected and analyzed for its chloride concentration. The procedure does not require a needle to collect the sweat.
Sweat chloride results are interpreted according to established diagnostic thresholds and the person’s clinical circumstances. A chloride concentration of 60 mmol/L or higher supports a diagnosis of CF in the appropriate clinical setting, while results below 30 mmol/L generally make CF less likely. Intermediate results require further evaluation, which may include repeat sweat testing, more extensive CFTR genetic analysis, or other specialized testing.
Carrier Screening
Carrier screening can determine whether a person carries a disease-causing CFTR variant. It may be offered before or during pregnancy, particularly to people with a family history of CF or those who want more information about their reproductive risk.
A carrier usually has one disease-causing CFTR variant and does not have cystic fibrosis. If both reproductive partners are carriers, each pregnancy has a 25% chance of resulting in a child with CF, a 50% chance of resulting in a child who is a carrier, and a 25% chance of resulting in a child who inherits neither of the parental disease-causing variants. Genetic counseling can help individuals and families understand test results and reproductive options.
Other Tests
After CF is diagnosed, additional testing helps clinicians assess which organs are affected and monitor the disease over time. Pulmonary function tests measure how well the lungs are working, while respiratory cultures can identify bacteria or other microorganisms in the airways. Chest imaging may be used when clinically appropriate to evaluate structural changes in the lungs.
Blood and other laboratory tests may be used to evaluate liver function, nutritional status, blood glucose, and levels of fat-soluble vitamins such as vitamins A, D, E, and K. Tests of pancreatic function may also be performed when pancreatic insufficiency is suspected.
The exact tests and how often they are performed depend on a person’s age, symptoms, treatment, and overall health.
Treatment
There is currently no cure for cystic fibrosis, but treatment can address the underlying CFTR protein dysfunction in many people, control symptoms, reduce complications, and help preserve lung function and nutrition. Because CF affects people differently, treatment is individualized according to factors such as age, CFTR variants, lung function, infections, pancreatic function, and other complications.
Multidisciplinary Care and Support
CF is best managed by a multidisciplinary team with experience in the disease. Depending on a person’s needs, the care team may include pulmonologists, nurses, dietitians, respiratory or physical therapists, pharmacists, social workers, gastroenterologists, endocrinologists, and other specialists.
Regular follow-up allows the team to monitor lung function, respiratory infections, growth and nutrition, CF-related diabetes, liver disease, bone health, and other complications. Adolescents also need coordinated support as they transition from pediatric to adult CF care.
Vaccination
People with CF should generally receive routine vaccinations recommended for their age and health status. Vaccination is particularly important because respiratory infections can cause significant illness and may worsen lung disease. Depending on age and individual risk factors, recommended vaccines may include seasonal influenza, COVID-19, pneumococcal, pertussis, and other routinely recommended immunizations.
A person’s CF care team can advise which vaccines and schedules are appropriate based on age, previous vaccination history, transplantation status, and other medical factors.
Airway Clearance and Physical Therapy
Airway clearance techniques help move thick mucus out of the lungs. Depending on the individual, these may include chest physiotherapy, positive expiratory pressure devices, oscillating devices, or other techniques recommended by the CF care team.
Regular physical activity can also support cardiovascular fitness and airway clearance, although exercise does not necessarily replace prescribed airway clearance therapy.
Inhaled therapies are commonly used as part of CF respiratory care. Hypertonic saline helps hydrate airway secretions and can make mucus easier to clear. Dornase alfa is another inhaled medication that reduces the thickness of mucus by breaking down extracellular DNA within airway secretions.
Medications for Respiratory Management
Respiratory medications are selected according to a person’s symptoms, lung function, airway cultures, and other medical conditions.
Bronchodilators may be prescribed for some people, particularly when airway narrowing or asthma-like symptoms are present. Anti-inflammatory treatment is more selective. High-dose ibuprofen may be considered for certain younger patients with preserved lung function under specialist supervision, but careful monitoring is required. Routine systemic or inhaled corticosteroids are generally not recommended solely for CF lung disease, although they may be appropriate when another condition, such as asthma or allergic bronchopulmonary aspergillosis (ABPA), provides a separate indication.
Antibiotics play an important role in treating and controlling respiratory infections in CF. The choice of antibiotic depends on factors such as the microorganism identified in respiratory cultures, previous infections, antibiotic susceptibility, symptoms, and the severity of illness. Depending on the situation, antibiotics may be inhaled, taken by mouth, or administered intravenously.
Pseudomonas aeruginosa is an important respiratory pathogen in CF. Specific antibiotic strategies may be used when it is detected for the first time and when chronic infection develops. Antibiotic treatment should therefore be directed by the CF care team rather than based on a single antibiotic regimen for everyone.
CFTR Modulators
CFTR modulators target abnormalities in the CFTR protein and can treat the underlying protein dysfunction in people with eligible CFTR variants.
Available CFTR modulator therapies include ivacaftor (Kalydeco), lumacaftor/ivacaftor (Orkambi), tezacaftor/ivacaftor (Symdeko), elexacaftor/tezacaftor/ivacaftor (Trikafta), and vanzacaftor/tezacaftor/deutivacaftor (Alyftrek).
These medications do not work for every CFTR variant, and eligibility varies according to the specific drug, genotype, age, and current regulatory approval. Genetic testing therefore helps determine whether a person may benefit from a CFTR modulator. Appropriate clinical and laboratory monitoring is also required during treatment.
Digestive and Nutritional Support
Many people with CF have pancreatic insufficiency, which prevents enough digestive enzymes from reaching the intestine. Pancreatic enzyme replacement therapy (PERT) is taken with meals and snacks to help digest and absorb nutrients.
Nutritional treatment is individualized according to growth, weight, pancreatic function, nutritional status, and other health needs. Some people require additional calories or supplementation with fat-soluble vitamins A, D, E, and K.
Constipation and other gastrointestinal complications can also occur and may require specific treatment. Intestinal obstruction, including meconium ileus in newborns or distal intestinal obstruction syndrome in older patients, may require urgent medical treatment and, in some cases, surgery.
Cystic Fibrosis-Related Diabetes
Some people with CF develop cystic fibrosis-related diabetes (CFRD). CFRD is a distinct form of diabetes and should not simply be classified as type 1 or type 2 diabetes. Reduced insulin production is an important cause, although insulin resistance can also contribute.
Because CFRD can develop without obvious symptoms, routine screening is an important part of CF care. Insulin is the standard treatment for CFRD, and nutritional management should be coordinated with clinicians experienced in both cystic fibrosis and diabetes.
Advanced Treatments and Transplantation
People with advanced CF lung disease may be evaluated for lung transplantation when other treatments are no longer sufficient. Transplantation does not cure the underlying genetic condition, but donor lungs do not have the recipient’s CFTR gene variants and therefore do not develop CF lung disease in the same way.
Some people with severe CF-related liver disease may also require liver transplantation. Decisions about transplantation require extensive evaluation at a specialist transplant center and consideration of the potential benefits, risks, and need for lifelong anti-rejection treatment.
Complications
Cystic fibrosis can cause complications in several organ systems. The type and severity of these complications vary considerably between individuals and can change with age.
Lung and Respiratory Complications
Chronic airway inflammation and repeated respiratory infections can gradually damage the lungs and lead to bronchiectasis, a condition in which the airways become permanently widened and more prone to mucus accumulation and infection. Some people experience pulmonary exacerbations, during which respiratory symptoms and lung function worsen and additional treatment may be needed.
Pneumothorax is another possible complication, particularly in people with more advanced lung disease. It occurs when air leaks into the space between the lung and chest wall and can cause part or all of a lung to collapse. Coughing up blood, known as hemoptysis, can also occur when damaged airway blood vessels bleed. Significant chest pain, sudden difficulty breathing, or coughing up large amounts of blood requires urgent medical attention.
Digestive and Nutritional Complications
Many people with CF develop pancreatic insufficiency, which reduces the digestion and absorption of nutrients. Without adequate treatment, this can contribute to poor growth, difficulty maintaining weight, and deficiencies of the fat-soluble vitamins A, D, E, and K.
Vitamin and nutritional deficiencies can contribute to complications such as reduced bone mineral density, osteoporosis, vision problems related to vitamin A deficiency, and abnormal bleeding associated with vitamin K deficiency. Pancreatic enzyme replacement and appropriate nutritional and vitamin supplementation can help reduce these risks.
People with CF can also develop intestinal complications. Meconium ileus may occur in newborns, while older children and adults can develop distal intestinal obstruction syndrome (DIOS), in which thick intestinal contents partially or completely block the intestine.
Cystic Fibrosis-Related Diabetes
Cystic fibrosis-related diabetes (CFRD) is a common complication of CF, particularly in adults. It develops mainly because damage to the pancreas reduces insulin production, although insulin resistance can also contribute.
CFRD is distinct from both type 1 and type 2 diabetes. It may initially cause few noticeable symptoms, which is why routine screening is an important part of CF care. Insulin is the standard treatment once CFRD is diagnosed.
Liver and Gallbladder Complications
CF can affect the liver and bile ducts when thick secretions interfere with normal bile flow. Some people develop CF-related liver disease, which can range from mild abnormalities in liver tests to more serious liver damage. Advanced disease can lead to cirrhosis, portal hypertension, and complications such as enlarged veins in the esophagus or stomach.
Gallbladder disease and gallstones can also occur. Treatment depends on the severity of symptoms and complications, and some people with advanced liver disease may eventually require evaluation for transplantation.
Bone Health
Low bone mineral density, osteopenia, and osteoporosis are more common in people with CF. Several factors can contribute, including inadequate nutrition, vitamin D deficiency, chronic inflammation, reduced physical activity, delayed puberty, and treatment with corticosteroids when these medications are required for other conditions.
Monitoring bone health and maintaining adequate nutrition, vitamin D and calcium intake, weight-bearing activity, and appropriate medical treatment can help reduce the risk of fractures.
Fertility and Reproductive Health
CF can affect fertility, although it generally does not prevent normal sexual function. Most men with CF are infertile because the vas deferens — the ducts that normally transport sperm from the testes — are absent or blocked, a condition known as congenital bilateral absence of the vas deferens (CBAVD). Most affected men still produce sperm, and assisted reproductive techniques may make biological parenthood possible.
Women with CF can become pregnant, although thickened cervical mucus and other health factors may reduce fertility in some people. Improvements in overall health and the use of highly effective CFTR modulators may also affect fertility and pregnancy planning.
People with CF who are considering pregnancy or biological parenthood should discuss reproductive health, medications, genetic counseling, and available fertility options with their CF care team.
Current Research Directions
Current cystic fibrosis research is increasingly focused on treatments that address the underlying cause of the disease. CFTR modulators already improve the function of defective CFTR protein in many people with eligible variants, but they do not work for everyone. Researchers are therefore investigating treatments that could potentially benefit people regardless of their specific CFTR variant.
These experimental approaches include gene addition, gene editing, and messenger RNA (mRNA) therapies. Gene-addition strategies aim to deliver a functional copy of the CFTR gene to airway cells, while gene-editing approaches seek to correct or modify disease-causing genetic variants. mRNA therapies take a different approach by delivering genetic instructions that allow cells to temporarily produce functional CFTR protein. These strategies remain investigational and must demonstrate acceptable safety and meaningful clinical benefit in human trials before they can become routine treatments.
Researchers are also investigating targets outside the CFTR protein. One example is the epithelial sodium channel (ENaC), which helps regulate salt and water movement across airway surfaces. Excessive sodium absorption may contribute to airway dehydration and thick mucus in CF, so researchers have explored whether inhibiting ENaC could improve airway hydration and mucus clearance. ENaC-targeted treatments remain experimental and are not currently established standard therapy for cystic fibrosis.
The development of these mutation-independent approaches is particularly important for people who cannot benefit from currently available CFTR modulators. However, results from laboratory studies and early clinical trials should not be interpreted as proof that a treatment is safe or effective until larger clinical studies confirm those findings.
Emerging Treatments and Therapies for Cystic Fibrosis
Cystic fibrosis research continues to focus on improving CFTR modulator therapy and developing treatments for people who cannot benefit adequately from existing modulators. Some approaches target the CFTR protein, while others use mRNA or gene-delivery technologies in an attempt to restore functional CFTR in airway cells.
It is important to distinguish approved treatments from experimental therapies. Investigational treatments must undergo clinical testing to determine whether they are safe and effective, and some promising programs do not ultimately advance.
Recently Approved CFTR Modulator
- Alyftrek (vanzacaftor/tezacaftor/deutivacaftor): Alyftrek is a once-daily CFTR modulator that was originally approved by the FDA in December 2024 for eligible people with cystic fibrosis aged 6 years and older. In March 2026, the FDA expanded its indication to include people aged 6 years and older with a clinical diagnosis of CF and at least one CFTR variant that is responsive based on clinical or laboratory data or results in production of CFTR protein, as specified in the approved labeling. Eligibility depends on a person’s CFTR variant and other prescribing criteria, so current FDA-approved prescribing information should be used when determining whether Alyftrek is appropriate.
Investigational Genetic and mRNA Therapies
- RCT2100 (inhaled mRNA therapy): RCT2100 is an investigational inhaled mRNA therapy designed to deliver instructions for producing functional CFTR protein in airway cells. The approach is being studied for people with CF who may not benefit from existing CFTR modulators. RCT2100 has received FDA orphan drug designation, but that designation does not mean the treatment has been approved or proven effective. Clinical studies are evaluating its safety and biological activity.
- BI 3720931 (inhaled gene therapy): BI 3720931 is an investigational inhaled gene therapy designed to deliver a functional CFTR gene to airway cells. Early-stage clinical research is evaluating its safety and potential effects in people with CF. Participants who received the therapy in an earlier study are also being followed in a long-term study to monitor safety and durability. The treatment remains experimental and has not been approved for routine clinical use.
- SION-719 (NBD1 stabilizer): Sionna Therapeutics is evaluating SION-719, an investigational small molecule designed to stabilize nucleotide-binding domain 1 (NBD1), a region of the CFTR protein affected by the F508del variant. Enrollment has been completed in the Phase 2a PreciSION CF proof-of-concept trial, which is evaluating SION-719 as an add-on to Trikafta in adults with CF who are homozygous for F508del. The study is assessing safety, tolerability, pharmacokinetics, and changes in sweat chloride as a measure of CFTR function. SION-719 remains investigational and has not been approved for the treatment of cystic fibrosis.
- 4D-710 (investigational gene therapy): 4D-710 is an investigational aerosol-delivered gene therapy currently being evaluated in a Phase 1/2 clinical trial in adults with cystic fibrosis lung disease. It is designed to deliver a CFTR transgene to airway cells and address the underlying CFTR defect. The study includes adults who are ineligible for or unable to tolerate CFTR modulators, as well as a substudy involving some adults receiving modulator therapy who have advanced lung disease or frequent pulmonary exacerbations. Researchers are evaluating safety, tolerability, biological activity, and preliminary effectiveness. 4D-710 has not been approved for routine treatment of cystic fibrosis. The approach is intended to address the underlying CFTR defect and may ultimately be relevant to people who cannot adequately benefit from CFTR modulators. Clinical studies are evaluating its safety, tolerability, biological activity, and potential effectiveness. It has not been approved for routine treatment of cystic fibrosis.
VX-522: Development Discontinued
VX-522 was an investigational inhaled mRNA therapy developed to deliver CFTR mRNA to lung cells, allowing those cells to produce functional CFTR protein. The approach was particularly relevant to people with CF variants that do not respond to existing CFTR modulators.
However, the VX-522 program is no longer in active development. A Phase 2 study was stopped early because of tolerability issues, and development of VX-522 for cystic fibrosis was discontinued. This illustrates why encouraging results from early-stage research should not be interpreted as evidence that an experimental therapy will ultimately become an approved treatment.
Despite setbacks involving individual programs, research into gene delivery, mRNA therapy, CFTR protein stabilization, and other mutation-independent approaches continues. These strategies are particularly important for people whose CFTR variants are not adequately addressed by currently available modulators.
Clinical opinion
Preventing respiratory infections is an important part of cystic fibrosis care. Nebulizers and other respiratory equipment can become contaminated if they are not cleaned, disinfected, dried, and stored correctly.
I advise patients and families to follow the cleaning and disinfection instructions provided by their CF care team and the equipment manufacturer, since the correct method can vary by device. Nebulizer components should be cleaned and disinfected as recommended and allowed to dry completely before storage.
The daily treatment burden of CF can be substantial. When appropriate, family members or caregivers can help with practical tasks, but anyone assisting with respiratory equipment should understand the correct hygiene procedures. If keeping up with the treatment routine becomes difficult, patients should discuss this with their CF care team, which may be able to suggest practical ways to manage the treatment burden while maintaining safe and effective care.
Bottom Line
Cystic fibrosis remains a serious lifelong genetic condition, but the outlook has improved substantially. Newborn screening, specialized multidisciplinary care, better nutritional and respiratory management, and especially CFTR modulator therapies have enabled many people with CF to live longer and healthier lives.
Treatment varies from person to person. CFTR modulators can address the underlying protein dysfunction in many people with eligible CFTR variants, but they do not work for everyone. Airway clearance, treatment of respiratory infections, pancreatic enzyme replacement, nutritional support, screening for cystic fibrosis-related diabetes, and management of other complications therefore remain important parts of care.
Researchers are also studying gene-delivery, gene-editing, mRNA, and other approaches that could potentially help people who do not benefit adequately from currently available CFTR modulators. These treatments remain experimental. Some research programs progress while others are discontinued because of safety, tolerability, or effectiveness concerns, as occurred with the investigational VX-522 mRNA program.
Access to treatment is another important challenge. The availability and affordability of CFTR modulators and specialized CF care vary between countries and health systems. Continued progress in CF care therefore depends not only on developing new treatments but also on determining their long-term safety and effectiveness and making effective care accessible to the people who need it.
People with CF should work with a specialized cystic fibrosis care team to develop an individualized treatment plan based on their CFTR variants, symptoms, complications, age, and overall health.
Frequently Asked Questions About Cystic Fibrosis
Cystic Fibrosis Basics
What is cystic fibrosis?
Cystic fibrosis (CF) is an inherited genetic condition caused by disease-causing variants in the CFTR gene. Abnormal CFTR protein function disrupts the movement of salt and water across cell surfaces, leading to thick secretions that can affect the lungs, pancreas, intestines, liver, reproductive system, and other organs.
Is cystic fibrosis contagious?
No. Cystic fibrosis is not contagious and cannot be transmitted through coughing, touching, kissing, sharing food, or living with someone who has CF. A person is born with CF because they inherited disease-causing CFTR variants from their biological parents.
Is cystic fibrosis an autoimmune disease?
No. Cystic fibrosis is a genetic disease, not an autoimmune disease. It results from variants in the CFTR gene rather than the immune system mistakenly attacking the body’s own tissues.
Can people of any race or ethnicity have cystic fibrosis?
Yes. People of every racial and ethnic background can have cystic fibrosis. Although CF has historically been diagnosed more frequently in people of European ancestry, it also occurs in Black, Hispanic, Asian, Indigenous, Middle Eastern, and other populations.
Genetics and Inheritance
How is cystic fibrosis inherited?
Cystic fibrosis is usually inherited in an autosomal recessive pattern. A person typically develops CF after inheriting a disease-causing CFTR variant from each biological parent.
What happens if both parents are cystic fibrosis carriers?
If both biological parents carry a disease-causing CFTR variant, each pregnancy has a 25% chance of resulting in a child with CF, a 50% chance of resulting in a child who is a carrier, and a 25% chance of resulting in a child who inherits neither parental disease-causing variant.
These probabilities apply independently to each pregnancy. Having one child with or without CF does not change the probabilities for the next pregnancy.
Can two healthy parents have a child with cystic fibrosis?
Yes. CF carriers usually do not have cystic fibrosis and may not know they carry a disease-causing CFTR variant. Two parents who are healthy carriers can therefore have a child with CF.
Can someone be a cystic fibrosis carrier without knowing it?
Yes. Most CF carriers do not have cystic fibrosis and may never know they carry a disease-causing CFTR variant unless they undergo genetic testing or the variant is identified because of their family history.
Symptoms and Diagnosis
What are the first signs of cystic fibrosis?
Possible early signs of cystic fibrosis include unusually salty-tasting skin, poor weight gain, difficulty growing, bulky or greasy stools, persistent coughing, wheezing, and recurrent respiratory infections. Some newborns develop meconium ileus, an intestinal blockage that can be an early sign of CF.
Symptoms vary considerably, and newborn screening can identify many babies before noticeable symptoms develop.
Can cystic fibrosis be diagnosed in adults?
Yes. Although newborn screening identifies many cases early in life, some people with less typical symptoms or certain CFTR variants are not diagnosed until adolescence or adulthood.
Adults with unexplained bronchiectasis, recurrent respiratory infections, chronic sinus disease, recurrent pancreatitis, or certain fertility problems may be evaluated for CF when clinically appropriate.
What is the main test for cystic fibrosis?
The sweat chloride test is the standard diagnostic test for cystic fibrosis. It measures the concentration of chloride in sweat.
A sweat chloride concentration of 60 mmol/L or higher supports a diagnosis of CF in the appropriate clinical setting. Intermediate results require additional evaluation, which may include repeat sweat testing, genetic testing, or other specialized tests.
Does a positive newborn screening result mean a baby has cystic fibrosis?
No. A positive newborn screening result does not by itself mean that a baby has cystic fibrosis. It identifies babies who need further evaluation.
A diagnostic sweat chloride test is typically performed after a positive newborn screen, and genetic testing may also be used.
Can genetic testing diagnose cystic fibrosis?
Genetic testing can help establish a cystic fibrosis diagnosis by identifying disease-causing variants in the CFTR gene. It is particularly useful when sweat test results are unclear or when a person’s symptoms strongly suggest CF.
Because many different CFTR variants exist, more extensive genetic analysis may sometimes be necessary when initial testing does not provide a clear answer.
Lung and Digestive Problems
Why does cystic fibrosis cause lung infections?
Cystic fibrosis causes abnormally thick airway secretions that are more difficult to clear from the lungs. Microorganisms can become trapped in these secretions, contributing to recurrent or chronic respiratory infections and inflammation.
Over time, repeated infections and inflammation can damage the airways and contribute to bronchiectasis and declining lung function.
Why is Pseudomonas aeruginosa important in cystic fibrosis?
Pseudomonas aeruginosa is a bacterium that can establish persistent infection in the airways of people with CF and contribute to inflammation and lung damage.
Respiratory cultures help CF care teams detect Pseudomonas and other microorganisms so treatment can be selected according to the patient’s clinical circumstances and culture results.
Why do some people with cystic fibrosis have trouble gaining weight?
Many people with CF have pancreatic insufficiency, which prevents enough digestive enzymes from reaching the small intestine. As a result, the body may have difficulty digesting and absorbing fats, proteins, vitamins, and calories.
Pancreatic enzyme replacement therapy and individualized nutritional support can help improve digestion and nutrient absorption.
What is pancreatic enzyme replacement therapy?
Pancreatic enzyme replacement therapy (PERT) provides digestive enzymes to people whose pancreas does not release enough enzymes into the intestine.
PERT is generally taken with meals and snacks to help the body digest food and absorb nutrients. The appropriate dose should be individualized with the person’s CF care team.
Cystic Fibrosis Treatment
Is there a cure for cystic fibrosis?
No cure for cystic fibrosis is currently available. However, treatment has improved substantially and can address many aspects of the disease.
Depending on the individual, treatment may include CFTR modulators, airway clearance, inhaled therapies, antibiotics, pancreatic enzyme replacement, nutritional support, insulin for cystic fibrosis-related diabetes, and treatment of other complications. Researchers are also studying gene, mRNA, and other approaches that could address the underlying cause of CF.
What are CFTR modulators?
CFTR modulators are medications designed to improve the function of defective CFTR protein in people with eligible CFTR variants.
Available CFTR modulator therapies include ivacaftor, lumacaftor/ivacaftor, tezacaftor/ivacaftor, elexacaftor/tezacaftor/ivacaftor, and vanzacaftor/tezacaftor/deutivacaftor.
Eligibility depends on factors including a person’s CFTR variants, age, and the approved indication for the particular medication.
What is the difference between Trikafta and Alyftrek?
Trikafta and Alyftrek are both CFTR modulator therapies, but they contain different combinations of medications.
Trikafta contains elexacaftor, tezacaftor, and ivacaftor. Alyftrek contains vanzacaftor, tezacaftor, and deutivacaftor. Alyftrek is taken once daily, while Trikafta uses morning and evening dosing.
Which treatment is appropriate depends on factors such as a person’s CFTR variants, age, clinical circumstances, potential drug interactions, and current prescribing information.
Does everyone with cystic fibrosis qualify for CFTR modulators?
No. CFTR modulators do not work for every disease-causing CFTR variant. Eligibility depends on whether a person’s variant is responsive to a particular therapy under its approved indication.
This is one reason genetic testing has become increasingly important in CF treatment. Researchers are also developing treatments intended to help people whose variants are not adequately addressed by existing modulators.
Do people still need airway clearance after starting CFTR modulators?
Some people taking highly effective CFTR modulators may still need airway clearance or other respiratory therapies. Researchers continue to study whether certain established treatments can be safely reduced in selected patients receiving highly effective modulators.
People should not stop prescribed airway clearance, inhaled medications, or other CF treatments without discussing the change with their CF care team.
Why are antibiotics used in cystic fibrosis?
Antibiotics are used to treat, eradicate, or suppress certain bacterial respiratory infections in people with CF. Depending on the infection and clinical situation, antibiotics may be inhaled, taken by mouth, or administered intravenously.
Antibiotic selection depends on factors such as respiratory culture results, the microorganism involved, previous infections, antibiotic susceptibility, symptoms, and severity of illness.
Complications and Other Health Conditions
What is cystic fibrosis-related diabetes?
Cystic fibrosis-related diabetes (CFRD) is a form of diabetes associated specifically with CF. It develops primarily because pancreatic damage reduces insulin production, although insulin resistance can also contribute.
CFRD is distinct from both type 1 and type 2 diabetes. It can develop without obvious symptoms, which is why routine screening is important. Insulin is the standard treatment after CFRD is diagnosed.
Can cystic fibrosis affect the liver?
Yes. Cystic fibrosis can affect the liver and bile ducts. Some people develop CF-related liver disease, which can range from relatively mild abnormalities to more serious complications.
Advanced disease can cause cirrhosis and portal hypertension. Liver health is therefore monitored as part of ongoing CF care.
Does cystic fibrosis affect bones?
Yes. People with cystic fibrosis have an increased risk of reduced bone mineral density, osteopenia, osteoporosis, and fractures.
Contributing factors can include nutritional deficiencies, vitamin D deficiency, chronic inflammation, reduced physical activity, delayed puberty, and exposure to certain medications. Nutrition, physical activity, vitamin status, and bone health may therefore require ongoing monitoring.
Why does cystic fibrosis cause chronic sinus problems and nasal polyps?
Cystic fibrosis can cause thick secretions to build up in the sinuses, interfering with normal drainage and contributing to chronic inflammation and infection. Some people with CF also develop nasal polyps, which are noncancerous growths of inflamed tissue inside the nose or sinuses.
Treatment depends on symptoms and severity and may include saline nasal irrigation, medications, and, in some cases, sinus surgery. People with persistent nasal congestion, facial pressure, reduced sense of smell, or recurrent sinus infections should discuss these symptoms with their CF care team or an ear, nose, and throat specialist.
Fertility, Pregnancy, and Family Planning
Can men with cystic fibrosis have biological children?
Yes, biological parenthood may be possible even though most men with CF are infertile because the vas deferens — the ducts that normally transport sperm — are absent or blocked.
Many men with CF still produce sperm. Sperm retrieval combined with assisted reproductive techniques may allow some to have biological children.
Can women with cystic fibrosis become pregnant?
Yes. Many women with cystic fibrosis can become pregnant. Fertility may be reduced in some women, but improvements in overall health and CF treatment have made pregnancy increasingly common.
Pregnancy should be planned with the CF care team because lung function, nutritional status, cystic fibrosis-related diabetes, medications, and other health factors can affect pregnancy management.
Can CFTR modulators affect fertility?
CFTR modulator therapy may increase fertility in some women with cystic fibrosis, potentially because of improvements in CFTR function, cervical mucus, and overall health.
People taking CFTR modulators who could become pregnant should discuss contraception, pregnancy planning, and the benefits and potential risks of medications with their CF care team.
Can a person with cystic fibrosis pass the condition to their children?
A person with cystic fibrosis will pass a disease-causing CFTR variant to each biological child. Whether the child develops CF depends on the CFTR variants inherited from the other biological parent.
Genetic testing of the reproductive partner and genetic counseling can help prospective parents better understand the probability of having a child with CF or a child who is a carrier.
Daily Life With Cystic Fibrosis
Can people with cystic fibrosis exercise?
Yes. Regular physical activity is generally encouraged when appropriate because it can support cardiovascular fitness, muscle strength, bone health, and airway clearance.
The safest type and intensity of exercise depend on the individual’s health, lung function, and other complications. People with significant medical limitations should discuss exercise plans with their CF care team.
How can cystic fibrosis affect mental health?
Living with cystic fibrosis can affect emotional as well as physical health. Daily treatments, medical appointments, hospitalizations, concerns about disease progression, and the demands of managing a lifelong condition can contribute to anxiety, depression, stress, and treatment burden.
Mental health is therefore an important part of comprehensive CF care. People with CF and their caregivers should feel comfortable discussing changes in mood, anxiety, sleep, motivation, or ability to cope with the CF care team. Screening and appropriate psychological or psychiatric support can help identify and address mental health concerns.
Can people with cystic fibrosis travel or fly on airplanes?
Yes. Many people with cystic fibrosis can travel and fly safely, but preparation is particularly important for those with advanced lung disease or other significant complications.
Commercial aircraft cabins have lower oxygen availability than at sea level, which can be important for people with reduced lung function or low blood oxygen levels. Before flying, people who may be at risk of low oxygen should discuss their plans with their CF care team to determine whether additional assessment or supplemental oxygen is needed.
Travel planning should also account for medications, refrigeration when required, airway-clearance equipment, nebulizer supplies, infection-prevention practices, adequate hydration and salt intake, and access to medical care at the destination. Travelers should carry enough medication and essential supplies for the trip, with additional supplies when appropriate in case of delays.
Can people with cystic fibrosis go to school and work?
Yes. Many people with cystic fibrosis attend school, work, travel, have relationships, and participate in a wide range of everyday activities.
However, CF treatment can require substantial time each day, and respiratory infections, medical appointments, hospitalizations, and other complications can sometimes interfere with school or work. Appropriate accommodations may help some people manage these demands.
Can two people with cystic fibrosis spend time together?
People with CF are generally advised to avoid close contact with other people who have CF because certain bacteria and other microorganisms can spread between them. Some of these organisms can cause difficult-to-treat lung infections.
CF infection-prevention recommendations should be followed when people with CF are attending clinics, events, or other settings where they could encounter one another.
Why does the skin of someone with cystic fibrosis taste salty?
People with CF lose unusually high amounts of chloride and sodium in their sweat because the CFTR protein does not regulate salt movement normally.
This can make the skin taste noticeably salty and can increase the risk of salt depletion and dehydration, particularly during hot weather, exercise, fever, or illness.
Life Expectancy and Outlook
How long can someone with cystic fibrosis live?
Survival has improved dramatically, and many people with cystic fibrosis now live well into adulthood. However, there is no single life-expectancy number that can accurately predict how long an individual person with CF will live.
Outcomes depend on factors such as CFTR variants, lung function, respiratory infections, nutritional status, complications, response to treatment, access to specialized care, and future advances in therapy. Population survival estimates should not be interpreted as an individual’s personal prognosis.
Is cystic fibrosis getting easier to treat?
Treatment options have improved substantially, particularly with the development of highly effective CFTR modulators. Better infection management, nutritional support, newborn screening, multidisciplinary care, and monitoring of complications have also contributed to improved outcomes.
CF nevertheless remains a complex lifelong disease, and treatment burden can still be substantial. Current therapies also do not adequately address every CFTR variant.
Gene Therapy and Future Treatments
Is gene therapy available for cystic fibrosis?
Gene therapy for cystic fibrosis remains investigational and is not currently an established approved treatment. Researchers are studying approaches designed to deliver functional CFTR genetic material to airway cells.
Experimental gene therapies must demonstrate acceptable safety and meaningful clinical benefit in clinical trials before they can become routine treatments.
Could gene editing cure cystic fibrosis?
Gene editing is being investigated as a possible way to correct or overcome disease-causing CFTR variants, but it has not been proven to cure cystic fibrosis in routine clinical practice.
Important challenges include safely delivering gene-editing systems to enough of the appropriate cells, achieving durable effects, and establishing long-term safety.
What are mRNA treatments for cystic fibrosis?
Experimental mRNA therapies are designed to provide cells with temporary genetic instructions for producing functional CFTR protein. Unlike gene editing, mRNA therapy does not need to permanently alter a person’s DNA.
The approach remains experimental. Individual mRNA programs may succeed or fail during clinical development, so promising laboratory or early clinical findings do not guarantee that a treatment will ultimately be approved.
Why are new cystic fibrosis treatments needed if CFTR modulators work?
CFTR modulators have transformed treatment for many people with cystic fibrosis, but they do not adequately treat every person or every CFTR variant.
Researchers are therefore investigating gene delivery, gene editing, mRNA therapies, new CFTR modulators, and other approaches that could potentially work independently of a person’s specific variant or provide additional benefit beyond existing treatments.
The long-term goal is to develop safe and effective treatments that address the underlying disease for as many people with cystic fibrosis as possible.
Advanced Cystic Fibrosis and Transplantation
Does a lung transplant cure cystic fibrosis?
No. A lung transplant does not cure cystic fibrosis. The transplanted lungs come from a donor without CF and therefore do not develop cystic fibrosis lung disease in the same way as the recipient’s original lungs. However, the person’s underlying CFTR gene variants remain present in cells elsewhere in the body.
CF can therefore continue to affect organs and systems outside the transplanted lungs, including the pancreas, intestines, sinuses, liver, and reproductive system. Some CF-related conditions, such as pancreatic insufficiency or cystic fibrosis-related diabetes, may still require treatment after transplantation.
Lung transplant recipients also require lifelong specialist follow-up and immunosuppressive medications to reduce the risk of organ rejection. Transplantation is therefore a treatment for selected people with advanced CF lung disease, not a cure for the underlying genetic condition.
Related Reading:
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