Cystic fibrosis is an inherited condition in which the lungs and digestive system can become clogged with thick, sticky mucus.
It can cause problems with breathing and digestion from a young age. Over many years, the lungs become increasingly damaged and may eventually stop working properly.
Most cases of cystic fibrosis in the UK are now identified through screening tests carried out soon after birth. It’s estimated that 1 in every 2,500 babies born in the UK has cystic fibrosis.
A number of treatments are available to help reduce the problems caused by the condition, but unfortunately average life expectancy is reduced for people who have it.
Symptoms of cystic fibrosis tend to start in early childhood, although they can sometimes develop very soon after birth, or may not be obvious until adulthood.
Some of the main symptoms of cystic fibrosis can include:
People with the condition can also develop a number of related conditions, including diabetes, thin, weakened bones (osteoporosis) and liver problems.
Read more about the symptoms of cystic fibrosis
Cystic fibrosis is caused by a faulty gene that a child inherits from both of their parents.
The faulty gene means that some cells struggle to move salt and water across the cell wall. This, along with recurrent infections, can result in a build-up of thick, sticky mucus in the body’s tubes and passageways.
To be born with cystic fibrosis, a child has to inherit two copies of this faulty gene – one from each of their parents. Their parents will not usually have the condition themselves, because they will only carry one faulty gene and one that works normally.
If both parents carry the faulty gene, there’s a 25% chance that each child they have will be born with cystic fibrosis.
Read more about the causes of cystic fibrosis
Most cases of cystic fibrosis are now detected soon after birth through the newborn blood spot test.
This involves collecting a drop of blood from the baby’s heel and testing it for abnormalities that could indicate cystic fibrosis.
More tests will be needed to confirm the diagnosis, such as:
These tests can also be carried out in older children and adults with symptoms of cystic fibrosis who haven’t been screened previously.
If you have a family history of cystic fibrosis, you can be tested to determine if you’re at risk of having a child with the condition by checking if you’re a “carrier” of the faulty gene that causes it.
Read more about how cystic fibrosis is diagnosed
There’s currently no cure for cystic fibrosis, but a number of treatments are available to help control the symptoms, prevent complications, and make the condition easier to live with.
Possible treatments include:
A lung transplant may eventually be needed if the lungs become greatly damaged.
Read more about treating cystic fibrosis
Cystic fibrosis is a progressive condition, which means it tends to get worse over time.
Eventually the condition can be fatal if it leads to a serious infection or the lungs stop working properly.
The outlook for cystic fibrosis has improved considerably in recent years because of advancements in treatment, although most people with cystic fibrosis will have a shorter-than-average life expectancy.
Currently, about half of the people with cystic fibrosis will live past the age of 40. Children born with the condition nowadays are likely to live longer than this.
If you or your child has cystic fibrosis, your clinical team will pass information about you/your child on to the National Congenital Anomaly and Rare Diseases Registration Service (NCARDRS).
This helps scientists look for better ways to prevent and treat this condition. You can opt out of the register at any time.
Cystic fibrosis can cause a range of problems. The lungs and digestive system are the main areas that are affected.
Symptoms tend to start in early childhood, but sometimes they can develop soon after birth and very occasionally they may not be obvious until adulthood.
Nowadays, cystic fibrosis is usually diagnosed before symptoms appear, through screening tests carried out soon after birth. Read more about screening for cystic fibrosis.
The main problems associated with cystic fibrosis are outlined below.
Cystic fibrosis can cause sticky mucus to clog the lungs and airways. This can cause:
Over time, the lungs can become increasingly damaged and may eventually stop working properly.
The mucus can also block parts of the digestive system, which can affect how food travels through the gut and how it’s broken down or absorbed.
This can cause:
People with cystic fibrosis can also experience a number of other problems, including:
Cystic fibrosis is caused by a faulty gene that a child inherits from both their parents.
The faulty gene means that some cells struggle to move salt and water across the cell wall. This, along with recurrent infections, can result in a build-up of thick, sticky mucus in the body’s tubes and passageways – particularly the lungs and digestive system.
The condition is present from birth and cannot be caught from someone else who has it.
Genes come in pairs. You inherit one set from your mother and one set from your father.
To be born with cystic fibrosis, a child has to inherit a copy of the faulty gene from both of their parents.
This can happen if the parents are ‘carriers’ of the faulty gene. This means they don’t have cystic fibrosis themselves, but they can have a child with the condition if their partner also carries the faulty gene.
It’s estimated that around 1 in every 25 people in the UK are carriers of the faulty gene that causes cystic fibrosis.
If both parents are carriers, there’s a:
This is known as an autosomal recessive inheritance pattern.
Tests can be carried out to diagnose cystic fibrosis at any age.
Most cases are now detected soon after birth through newborn screening, but older children and adults with symptoms of cystic fibrosis who weren’t screened can also have tests to check for the condition.
Tests to find out if you are a ‘carrier’ of the faulty gene responsible for cystic fibrosis may also be recommended for some people.
A newborn blood spot test is offered to all babies in Scotland to help detect problems early on, including cystic fibrosis.
When your baby is five to eight days old, a health professional will prick their heel and collect drops of blood on a special card. The blood is then sent to a laboratory to be checked for abnormalities that could indicate cystic fibrosis.
You should receive the results by the time your baby is six to eight weeks old. You will be contacted sooner if a problem is found, and you’ll be asked to attend a hospital appointment.
The screening result isn’t 100% accurate, so more tests will be carried out to confirm the diagnosis. You, your partner and any other children you have may also be tested to see if you carry the faulty gene that causes cystic fibrosis.
Tests to confirm a diagnosis will be carried out if screening suggests that your child may have cystic fibrosis, or your doctor thinks you could have the condition and you haven’t been screened previously.
Two main tests can be used to diagnose cystic fibrosis:
The sweat test is most commonly used, although genetic testing may be done if the sweat test result is inconclusive or to identify the specific genetic fault that’s causing the condition.
Testing to find out if you carry the faulty gene that causes cystic fibrosis may be useful if:
This can be done using a blood test, or occasionally a special mouthwash, to collect a sample of cells. The sample is then sent to a laboratory so it can be checked for the faulty gene.
Finding out whether you’re a carrier of the faulty gene can help determine if you’re at risk of having a child with cystic fibrosis. A genetic counsellor will explain the results of the test to you and discuss the implications and options available for future pregnancies.
There’s currently no cure for cystic fibrosis, but it’s possible to help control the symptoms, prevent or reduce complications, and make the condition easier to live with.
A person with cystic fibrosis will be supported by a team of healthcare professionals at a specialist cystic fibrosis centre. A care plan will be drawn up that’s tailored to their individual needs.
A range of treatments may be used and sometimes treatment in hospital will be needed. Regular appointments to monitor the condition will also be recommended.
Some of the main treatments for cystic fibrosis include:
People with cystic fibrosis may need to take a number of different medicines to treat and prevent lung problems. These may be swallowed, inhaled or injected.
Some of the main medicines for cystic fibrosis are:
It’s also important that people with cystic fibrosis are up to date with all routine vaccinations and have the flu jab each year once they’re old enough.
In addition to medication, special techniques can be used to help keep the lungs and airways clear. A physiotherapist can give you advice.
Some of the main techniques include:
Your care team can provide more information on the techniques mentioned above.
For people with cystic fibrosis, getting the right nutrition is vital in helping them develop normally and stopping them becoming frequently ill.
However, the majority of people with cystic fibrosis cannot digest food and absorb nutrients from when they’re a baby. Occasionally, the condition can cause the pancreas to become damaged over time, causing the same problem.
A dietitian will advise on what you can do to help avoid malnutrition. They may recommend:
In severe cases of cystic fibrosis, when the lungs stop working properly and all medical treatments have failed to help, a lung transplant may be recommended.
A lung transplant is a serious operation that carries risks, but it can greatly improve the length and quality of life for people with severe cystic fibrosis.
The outlook for people with cystic fibrosis is often better than for many transplant patients, as they’re often younger and in better general health. It’s estimated that up to 9 out of 10 people will survive for at least a year after a transplant.
The Cystic Fibrosis Trust has information on lung transplants in cystic fibrosis.
People with cystic fibrosis can have a number of other problems that may benefit from treatment.
For example:
Last updated:
18 October 2023