Cystic fibrosis

Updated: 2024-12-07

Overview

Cystic fibrosis

Cystic fibrosis

In cystic fibrosis, the airways fill with thick, sticky mucus, making it difficult to breathe. The thick mucus is also an ideal breeding ground for bacteria and fungi.

Cystic fibrosis (CF) is a condition passed down in families that causes damage to the lungs, digestive system and other organs in the body.

CF affects the cells that make mucus, sweat and digestive juices. These fluids, also called secretions, are usually thin and slippery to protect the body's internal tubes and ducts and make them smooth pathways. But in people with CF, a changed gene causes the secretions to become sticky and thick. The secretions plug up pathways, especially in the lungs and pancreas.

CF gets worse over time and needs daily care, but people with CF usually can attend school and work. They often have a better quality of life than people with CF had in past decades. Better screening and treatments mean that people with CF now may live into their mid- to late 50s or longer, and some are being diagnosed later in life.

Symptoms

In the U.S., because of newborn screening, cystic fibrosis can be diagnosed within the first month of life, before symptoms develop. But people born before newborn screening became available may not be diagnosed until the symptoms of CF show up.

CF symptoms vary, depending on which organs are affected and how severe the condition is. Even in the same person, symptoms may worsen or get better at different times. Some people may not have symptoms until their teenage years or adulthood.

People who are not diagnosed until adulthood usually have milder symptoms and are more likely to have symptoms that aren't typical. These may include repeated bouts of an inflamed pancreas called pancreatitis, infertility and repeated bouts of pneumonia.

People with CF have a higher than usual level of salt in their sweat. Parents often can taste the salt when they kiss their children. Most of the other symptoms of CF affect the respiratory system and digestive system.

Respiratory symptoms

In cystic fibrosis, the lungs are most commonly affected. The thick and sticky mucus that happens with CF clogs the tubes that carry air in and out of the lungs. This can cause symptoms such as:

• A cough that won't go away and brings up thick mucus.
• A squeaking sound when breathing called wheezing.
• Limited ability to do physical activity before tiring.
• Repeated lung infections.
• Irritated and swollen nasal passages or a stuffy nose.
• Repeated sinus infections.

Digestive symptoms

The thick mucus caused by cystic fibrosis can block tubes that carry digestive enzymes from the pancreas to the small intestine. Without these digestive enzymes, the intestines can't completely take in and use the nutrients in food. The result is often:

• Foul-smelling, greasy stools.
• Poor weight gain and growth.
• Blocked intestines, which is more likely to happen in newborns.
• Ongoing or severe constipation. Straining often while trying to pass stool can cause part of the rectum to stick out of the anus. This is called a rectal prolapse.

When to see a doctor

If you or your child has symptoms of cystic fibrosis — or if someone in your family has CF — talk with your healthcare professional about testing for the condition. Make an appointment with a doctor who has skills and experience in treating CF.

CF requires regular follow-up with your healthcare professional, at least every three months. Call your healthcare professional if you have new or worsening symptoms, such as more mucus than usual or a change in the mucus color, lack of energy, weight loss, or severe constipation.

Get medical care right away if you're coughing up blood, have chest pain or trouble breathing, or have severe stomach pain and bloating.

Call 911 or your local emergency number or go to the emergency department at a hospital if:

• You're having a hard time catching your breath or talking.
• Your lips or fingernails turn blue or gray.
• Others notice that you're not mentally alert.

Causes

Autosomal recessive inheritance pattern

To have an autosomal recessive disorder, you inherit two changed genes, sometimes called mutations. You get one from each parent. Their health is rarely affected because they have only one changed gene. Two carriers have a 25% chance of having an unaffected child with two unaffected genes. They have a 50% chance of having an unaffected child who also is a carrier. They have a 25% chance of having an affected child with two changed genes.

In cystic fibrosis, a change in a gene causes problems with the protein that controls the movement of salt and water in and out of cells. This gene is the cystic fibrosis transmembrane conductance regulator (CFTR) gene. It affects the cells that make mucus, sweat and digestive juices. When the CFTR protein doesn't work as it should, the result is thick, sticky mucus in the respiratory, digestive and reproductive systems, as well as extra salt in sweat.

Changes in the CFTR gene that cause CF are divided into several different groups based on the problems they cause. Different groups of gene changes affect how much CFTR protein is made and how well it works.

To have cystic fibrosis, children must get one copy of the changed CFTR gene from each parent. If children get only one copy, they won't develop CF. But they will be carriers and could pass the changed gene to their own children. People who are carriers may have no symptoms of CF or a few mild symptoms.

Risk factors

Because cystic fibrosis is a condition passed down in families, family history is a risk factor.

CF occurs in all races, but it's most common in white people of Northern European ancestry. Because it's less common in people who are Black, Hispanic, Middle Eastern, Native American or Asian, this might lead to a much later diagnosis.

A late diagnosis may cause worse health issues. Early and effective treatment can improve your quality of life, prevent complications and help you live longer. If you're a person of color and have symptoms that could be CF, talk to your healthcare professional so that you can get tested for CF.

Complications

Complications of cystic fibrosis can affect the respiratory, digestive and reproductive systems, as well as other organs.

Respiratory system complications

• Damaged airways. Cystic fibrosis is one of the leading causes of damaged airways, a long-term lung condition called bronchiectasis. Bronchiectasis results in widening and scarring of the airways. This makes it harder to move air in and out of the lungs and clear mucus from the airways.
• Ongoing infections. Thick mucus in the lungs and sinuses makes a place for bacteria and fungi to live and grow. Sinus infections, bronchitis or pneumonia are common and may happen repeatedly. Infections with bacteria that don't respond to antibiotics and are difficult to treat is common too.
• Growths in the nose. Because the lining inside the nose is irritated and swollen, it can develop soft, fleshy growths called nasal polyps.
• Coughing up blood. Bronchiectasis can occur next to blood vessels in the lungs. The combination of airway damage and infection can result in coughing up blood. Often this is only a small amount of blood, but rarely it can be life-threatening.
• Collapsed lung. Also called pneumothorax, this condition happens when air leaks into the space that separates the lungs from the chest wall. This causes part or all of a lung to collapse. Collapsed lung is more common in adults with CF. Collapsed lung can cause sudden chest pain and trouble breathing. People often have a bubbling feeling in the chest.
• Respiratory failure. Over time, CF can damage lung tissue so badly that it no longer works. Lung function usually worsens slowly over time and can become life-threatening. Respiratory failure is the most common cause of death with CF.
• Bouts of worsening symptoms. People with CF may experience times when respiratory symptoms are worse than usual. These are called exacerbations (eg-zas-er-bay-shuns). Symptoms may include coughing with more mucus than usual and trouble breathing. Low energy and weight loss also are common during exacerbations. Exacerbations are treated with antibiotics. Sometimes treatment can be given at home, but a stay in the hospital may be needed.

Digestive system complications

• Poor nutrition. Thick mucus can block the tubes that carry digestive enzymes from the pancreas to the intestines. Without these enzymes, the body can't take in and use protein, fats or fat-soluble vitamins and can't get enough nutrients. This can result in delayed growth and weight loss. An inflamed pancreas, a condition called pancreatitis, is common.
• Diabetes. The pancreas makes insulin, which the body needs to use sugar. Cystic fibrosis raises the risk of diabetes. About 20% of teenagers and up to 50% of adults with CF develop diabetes.
• Liver disease. The tube that carries bile from the liver and gallbladder to the small intestine may become blocked and inflamed. This can lead to liver problems, such as jaundice, fatty liver disease and cirrhosis, and sometimes gallstones.
• Intestinal obstruction. Intestinal blockage can happen to people with CF at all ages. Sometimes, a condition in which a section of the intestine slides inside another nearby section of the intestine, like a collapsible telescope, also can happen.
• Distal intestinal obstruction syndrome (DIOS). DIOS is partial or complete blockage where the small intestine meets the large intestine. DIOS requires treatment right away.

Reproductive system complications

• Infertility in men. Almost all men with cystic fibrosis are not fertile. The tube that connects the testicles and prostate gland, called the vas deferens, is either blocked with mucus or missing entirely. Sperm is still made in the testicles even though it can't pass into the semen made by the prostate gland. Certain fertility treatments and surgical procedures sometimes make it possible for men with CF to become biological parents.
• Lower fertility in women. Although women with CF may be less fertile than other women, it's possible for them to conceive and to have successful pregnancies. Still, pregnancy can worsen the symptoms of CF. Talk with your healthcare professional about the risks.

Other complications

• Thinning of the bones. Cystic fibrosis raises the risk of developing a dangerous thinning of bones called osteoporosis. Joint pain, arthritis and muscle pain also may occur.
• Out of balance electrolytes and dehydration. CF causes saltier sweat, so the balance of minerals in the blood may be upset. This raises the risk for dehydration, especially with exercise or in hot weather. Symptoms of dehydration include a fast heartbeat, extreme tiredness, weakness and low blood pressure.
• Gastroesophageal reflux disease (GERD). Stomach acid repeatedly flows back up into the tube connecting the mouth and stomach, called the esophagus. This backwash is known as acid reflux, and it can irritate the lining of the esophagus.
• Mental health conditions. Having an ongoing medical condition that has no cure may cause fear, depression and anxiety.
• Higher risk of digestive tract cancer. The risk of cancer of the esophagus, stomach, small and large bowel, liver, and pancreas is higher in people with cystic fibrosis. Regular colorectal cancer screening should begin at age 40.

Prevention

If you or your partner have close relatives with cystic fibrosis, you both may choose to have genetic testing before having children. Testing done in a lab on a sample of blood can help find out your risk of having a child with CF.

If you're already pregnant and the genetic test shows that your baby may be at risk of CF, your healthcare professional can do other tests on your unborn child.

Genetic testing isn't for everyone. Before you decide to be tested, talk with a genetic counselor about the mental health impact the test results might have.

Diagnosis

To diagnose cystic fibrosis, healthcare professionals typically do a physical exam, review your symptoms and do tests.

Newborn screening and diagnosis

Every state in the U.S. now routinely screens newborns for cystic fibrosis. Early diagnosis means that treatment can begin right away. Testing can include:

• Newborn screening. In this screening test, a healthcare professional takes a few drops of blood from the baby's heel. A lab checks the blood sample for higher levels than expected of a chemical called immunoreactive trypsinogen (IRT). IRT is released by the pancreas and may suggest CF. A newborn's IRT levels also may be high because of premature birth or a stressful delivery. For that reason, other tests may be needed to confirm a diagnosis of cystic fibrosis.
• Sweat test. To check if a baby has CF, a sweat test is done once the baby is at least 2 weeks old. A chemical that causes the skin to sweat is put on a small area of skin. Then the sweat is collected to test it and see if it's saltier than typical. Testing done at a care center accredited by the Cystic Fibrosis Foundation helps ensure results that can be trusted.
• Genetic testing. Healthcare professionals also may recommend genetic testing to look for specific changes on the gene responsible for CF. Genetic testing may be used along with IRT levels to confirm the diagnosis.

Testing of older children and adults

Cystic fibrosis tests may be recommended for older children and adults who weren't screened at birth. Your healthcare professional may suggest genetic and sweat tests for CF if you have repeated bouts of an inflamed pancreas, nasal polyps, chronic sinus infections, lung infections, bronchiectasis or male infertility.

Treatment

Vest therapy

Using a personalized approach, a Mayo Clinic respiratory therapist discusses inflatable vest therapy with an adult who has cystic fibrosis.

There is no cure for cystic fibrosis, but treatment can ease symptoms, lessen complications and improve quality of life. Close monitoring and early, aggressive intervention is recommended to slow the worsening of CF over time. This can lead to a longer life.

Managing CF is complicated, so it's best to get treatment at a center with a multispecialty team of doctors and other healthcare professionals trained in CF. They can evaluate and treat your condition.

The goals of treatment include:

• Preventing and controlling infections that occur in the lungs.
• Removing and loosening mucus from the lungs.
• Treating and preventing intestinal blockage.
• Getting enough nutrition.

Medicines

Options include:

• Medicines that target gene changes and improve how the CFTR protein works. These are called cystic fibrosis transmembrane conductance regulator (CTFR) modulators.
• Antibiotics to treat and prevent lung infections.
• Anti-inflammatory medicines to lessen swelling in the airways in the lungs.
• Mucus-thinning medicines, such as hypertonic saline, to help cough up mucus. This can improve lung function.
• Medicines breathed into the lungs called bronchodilators. These can help keep airways open by relaxing the muscles around the bronchial tubes.
• Pancreatic enzyme capsules taken by mouth to help the digestive tract take in and use nutrients.
• Stool softeners to prevent constipation or bowel obstruction.
• Acid-reducing medicines to help pancreatic enzymes work better.
• Specific medicines for diabetes or liver disease, when needed.

Medicines that target genes

For those with cystic fibrosis who have certain gene changes, cystic fibrosis transmembrane conductance regulator (CFTR) modulators may help. About 90% of people with CF may be helped by using these medicines. Gene testing is needed to find out which specific gene change you have and if a CFTR modulator may work for you.

CFTR modulators are newer medicines that many experts think are a breakthrough in the treatment of CF. The medicines help the CFTR protein work better. This can make lung function better, help digestion and weight, and lessen the amount of salt in sweat.

The U.S. Food and Drug Administration (FDA) has approved these CFTR modulators for treating CF in people with specific changes in the CFTR gene:

• The newest combination medicine with elexacaftor, ivacaftor and tezacaftor (Trikafta) is approved for people age 2 years and older. Trikafta has been shown to be the most effective CFTR modulator.
• The combination medicine with ivacaftor and tezacaftor (Symdeko) is approved for people age 6 years and older.
• The combination medicine with ivacaftor and lumacaftor (Orkambi) is approved for people who are age 1 year and older.
• Ivacaftor (Kalydeco) is approved for people who are 1 month and older.

Your healthcare professional may do liver function tests and eye exams before prescribing these medicines. While taking these medicines, you'll likely need testing on a regular basis to check for side effects such as liver function changes and clouding of the eye lenses called cataracts. Ask your healthcare professional and pharmacist for information on possible side effects and what to watch for.

Keep regular follow-up appointments so your healthcare professional can monitor you while taking these medicines. Tell your healthcare professional about any side effects that you have.

Airway clearance techniques

Airway clearance techniques, also called chest physical therapy, can help get rid of mucus blocking the airways. It also can help to lessen infection and inflammation in the airways. Airway clearance techniques loosen the thick mucus in the lungs, making it easier to cough up.

Airway clearing techniques are usually done several times a day. Different techniques, and often more than one method, can be used to loosen and remove mucus.

• Clapping with cupped hands on the front and back of the chest. This is a common technique.
• Special breathing and coughing activities.
• Mechanical devices, such as a tube that you blow into, and a machine that pulses air into the lungs called a vibrating vest.
• Vigorous exercise.

Your healthcare professional can give you instructions on the airway clearance techniques that are best for you and how often you should do them.

Pulmonary rehabilitation

Your healthcare professional may recommend a long-term program called pulmonary rehabilitation. The program may improve your lung function and your overall well-being. Pulmonary rehabilitation is usually done on an outpatient basis and may include:

• Physical exercise that may improve your condition.
• Breathing techniques that may help loosen mucus and make breathing easier.
• Dietary counseling.
• Mental health counseling and support.
• Education about your condition.

Surgery and other treatments

Options for certain conditions caused by cystic fibrosis include:

• Nasal and sinus surgery. Surgery can remove nasal polyps that get in the way of breathing. Sinus surgery may be done to treat repeated or long-term sinusitis.
• Oxygen therapy. If there isn't enough oxygen in your blood, you may need supplemental oxygen. You can get this extra oxygen to your lungs through a mask or through plastic tubing with tips that fit into your nose. These attach to an oxygen tank. Lightweight, portable units that you take with you can help you be more mobile. Oxygen therapy may prevent high blood pressure in the lungs, a condition called pulmonary hypertension.
• Noninvasive ventilation. Typically used while sleeping, noninvasive ventilation uses a nose or mouth mask to give positive pressure in the airway and lungs when breathing in. It's often used along with oxygen therapy. Noninvasive ventilation can increase air exchange in the lungs and lessen the work of breathing. The treatment also may help with airway clearance.
• Feeding tube. CF interferes with digestion, so you can't take in and use nutrients from food very well. A feeding tube delivers extra nutrition. This may be a short-term tube placed through your nose and guided to your stomach. Or the tube may be surgically placed in the stomach through a small cut in the skin on your belly. A feeding tube gives extra calories during the day or night and does not keep you from eating by mouth.
• Bowel surgery. If a blockage happens in the intestines, you may need surgery to remove it. If part of an intestine folds inside a nearby section of intestine, you may need surgery.

• Lung transplant. If you have severe breathing problems or life-threatening lung complications, or if antibiotics no longer work to treat lung infections, a lung transplant may be an option. Because bacteria line the airways in diseases such as CF that cause permanent widening of the large airways, both lungs need to be replaced.

  Cystic fibrosis does not recur in transplanted lungs. But other complications linked with CF, such as sinus infections, diabetes, pancreas conditions and osteoporosis, can still happen after a lung transplant.

• Liver transplant. For severe CF-related liver disease, such as cirrhosis, liver transplant may be an option. In some people, a liver transplant may be done together with lung or pancreas transplants.

Lifestyle and home remedies

Here are some ways you can manage cystic fibrosis and lessen complications.

Prevention

Pay attention to nutrition and fluid intake

Cystic fibrosis can cause poor nutrition because the enzymes needed for digestion can't reach the small intestine. This prevents food from being taken in and used by the body. People with CF may need a much higher number of calories daily than do people without the condition.

A healthy diet is important to growth and development and to support good lung function. It's also important to drink lots of fluids to help thin the mucus in your lungs. You may work with a dietitian to create a nutrition plan.

Your healthcare professional may recommend:

• Pancreatic enzyme capsules with every meal and snack.
• Medicines to lessen acid made in the stomach and help pancreatic enzymes work.
• High-calorie nutrition supplements.
• Special fat-soluble vitamins.
• Extra fiber to prevent intestinal blockage.
• Extra salt, especially during hot weather or before exercising.
• Drinking enough water, especially during hot weather.

Keep vaccinations up to date

In addition to the other usual childhood vaccines, the annual flu vaccine is important if you have cystic fibrosis. So are any other vaccines your healthcare professionals recommend, such as the vaccine to prevent pneumonia and COVID-19. CF doesn't affect the immune system, but people with CF are more likely to develop complications when they get sick.

Exercise

Regular exercise helps loosen mucus in your airways and makes your heart stronger. Because people with cystic fibrosis are living longer, it's important to keep your heart and blood vessels in good shape for a healthier life. Anything that gets you moving, including walking and biking, can help.

Stay away from smoke

Don't smoke, and don't allow other people to smoke around you or your child. Secondhand smoke and air pollution are harmful for everyone, but especially if you have cystic fibrosis. Using electronic cigarettes, also called vaping, can worsen CF too.

Wash your hands

Teach all the members of your family to wash their hands thoroughly before eating, after using the bathroom, when coming home from work or school, and after being around a sick person. If possible, stay away from people who have colds or flu. Washing your hands is the best way to protect against infection.

Keep medical appointments

Along with ongoing care from your medical team:

• Keep your regular follow-up appointments.
• Take your medicines as prescribed and follow therapies as instructed.
• Talk with your healthcare professional about how to manage symptoms.
• Learn the warning signs of serious complications.

Coping and support

If you or someone you love has cystic fibrosis, you may have strong emotions such as depression, anxiety, anger or fear. These feelings may be especially common in teens. These tips may help.

• Find support. Talking openly about how you feel can help. It also may help to talk with others who have the same condition. That might mean joining a support group for yourself or finding a support group for parents of children with cystic fibrosis. Older children with CF may want to join a CF group to meet and talk with others who have the condition.
• Get professional help. If you or your child is depressed or anxious, it may help to meet with a mental health professional. You can talk about feelings and ways to cope. The mental health professional may suggest medicines or other treatments too.
• Spend time with friends and family. Having their support can help you manage stress and lessen anxiety. Ask your friends or family for help when you need it.
• Take time to learn about cystic fibrosis. If your child has cystic fibrosis, encourage your child to learn about CF. Find out how medical care is managed for children with CF as they grow older and reach adulthood. Talk with your healthcare professional if you have questions about care.

Preparing for an appointment

Make an appointment with your healthcare professional if you or your child has symptoms common to cystic fibrosis. After the evaluation, you may be referred to a specialist trained in diagnosing and treating CF.

Here's some information to help you prepare for your appointment, as well as what to expect from your healthcare professional.

What you can do

You might want to take a friend or family member with you to the appointment to help you remember information.

Before your appointment, make a list of:

• Symptoms and when they started. Include anything that makes symptoms worse or better.
• All medicines, vitamins, herbs and supplements that you or your child take. Include the doses.
• Family history, such as whether anyone in your family has cystic fibrosis.
• Treatment you or your child have had for CF, if any. Include what the treatment was and if it helped.
• Any other medical conditions and their treatments.
• Questions to ask your healthcare professional.

Questions to ask may include:

• What is likely causing these symptoms?
• What kinds of tests are needed?
• What treatment do you recommend?
• I or my child have other health conditions. How will cystic fibrosis affect them?
• Are there any limits needed?

Feel free to ask other questions during your appointment.

What to expect from your doctor

After getting detailed information about the symptoms and your family's medical history, your healthcare professional may order tests to help with diagnosis and plan treatment.

Your healthcare professional also may ask questions, such as:

• What symptoms are you or your child having?
• When did the symptoms start?
• Does anything make the symptoms better or worse?
• Has anyone in your family ever had cystic fibrosis?
• Has growth been average and weight been stable?