Cystic fibrosisSee all parts of this guide Hide guide parts
About cystic fibrosis
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
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:
- recurring chest infections
- difficulty putting on weight
- frequent, wet-sounding coughs
- occasional wheezing and shortness of breath
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
Causes 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
Screening and testing for 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:
- a sweat test – to measure the amount of salt in sweat, as the sweat of someone with cystic fibrosis has higher levels of salt than normal
- a genetic test – where a sample of blood or saliva is checked for the faulty gene that causes cystic fibrosis
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
Treatments for cystic fibrosis
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:
- antibiotics to prevent and treat chest infections
- medicines to make the mucus in the lungs thinner and easier to cough up
- medicines to widen the airways and reduce inflammation
- special techniques and devices to help clear mucus from the lungs
- medicines that help the person absorb food better
- following a special diet and taking supplements to prevent malnutrition
A lung transplant may eventually be needed if the lungs become greatly damaged.
Read more about treating cystic fibrosis
Outlook for 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.
Information about you
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.
Symptoms of cystic fibrosis
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:
- recurring chest infections – these occur because mucus in the lungs is an ideal breeding ground for bacteria
- persistent inflammation of the airways, which can cause them to become abnormally widened (bronchiectasis)
- increased coughing
- occasional wheezing and shortness of breath
Over time, the lungs can become increasingly damaged and may eventually stop working properly.
Digestive system problems
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:
- a serious bowel obstruction in the first few days of life (meconium ileus) – this will often need an operation to remove the blockage
- diarrhoea or large, smelly stools
- problems putting on weight and growing – this can occur because the body struggles to digest and absorb nutrients (malnutrition)
- diabetes from late childhood or early adulthood – this can develop if the pancreas becomes severely damaged
People with cystic fibrosis can also experience a number of other problems, including:
- nasal polyps
- thin, weakened bones (osteoporosis) – this can occur as a result of repeated infections, poor growth, lack of physical activity and malnutrition
- swelling and pain in the joints (arthritis or arthralgia) from late childhood
- difficulty conceiving children – most men with cystic fibrosis are unable to have children naturally (although some fertility treatments may still work) because the tubes that carry sperm don't develop correctly; women can become pregnant, however
- liver problems caused by the tiny bile ducts in the liver becoming blocked by mucus
- leaking of small amounts of urine, particularly during coughing fits (stress incontinence)
Causes of cystic fibrosis
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.
How cystic fibrosis is inherited
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:
- 25% chance that each child they have will not inherit any faulty genes and won't have cystic fibrosis or be able to pass it on
- 50% chance that each child they have will just inherit one copy of the faulty gene from one parent and be a carrier
- 25% chance that each child they have will inherit copies of the faulty gene from both parents and will have cystic fibrosis
This is known as an autosomal recessive inheritance pattern.
Diagnosing cystic fibrosis
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.
Confirming a diagnosis
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:
- sweat test – a test to measure the amount of salt in sweat, as the sweat of someone with cystic fibrosis has higher levels of salt than normal
- genetic test – where a sample of blood or saliva is checked for the faulty gene that causes 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:
- you have a close relative, such as a child, sibling or parent, who's a known carrier
- you have a close relative with cystic fibrosis
- your partner is known to carry the cystic fibrosis gene
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.
Treating cystic fibrosis
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:
Medications for lung problems
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:
- antibiotics to prevent and treat chest infections
- medicines to make the sticky mucus in the lungs thinner, such as dornase alfa, hypertonic saline and mannitol dry powder
- a medicine called ivacaftor to help reduce the levels of mucus in the body – although this is only suitable for fewer than 1 in every 20 people (4%) with cystic fibrosis
- bronchodilators to widen the airways and help make breathing easier
- steroid medication to treat nasal polyps (small growths inside the nose)
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.
Airway clearance techniques
In addition to medication, special techniques can be used to help keep the lungs and airways clear. A physiotherpist can give you advice.
Some of the main techniques include:
- active cycle of breathing techniques (ACBT) – a technique that involves a sequence of relaxed breathing, followed by deep breathing exercises and then huffing
- autogenic drainage – a series of gentle breathing techniques that clear mucus from the lungs
- modified postural drainage – a technique that involves changing your position to make it easier to remove mucus from your lungs
- airway clearance devices – handheld devices that use vibration and air pressure to help remove mucus from your airways; you may have to pay in the region of £45-60 for one of these devices
Your care team can provide more information on the techniques mentioned above.
Dietary and nutritional advice
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:
- taking digestive enzyme capsules with all meals and snacks to help with digestion – the number of capsules needed depends on the food being eaten and varies from person to person
- following a special balanced diet that's high in calories (energy), fat and protein
- taking vitamin and mineral supplements
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.
Treatments for associated problems
People with cystic fibrosis can have a number of other problems that may benefit from treatment.
- exercise can help keep bones and joints healthy, and is recommended for everyone with cystic fibrosis – any sport or exercise is usually good, but if you're not sure about a particular activity, you should ask your physiotherapist for advice
- medicines called bisphosphonates can help treat weak and brittle bones that may occur as a result of cystic fibrosis if the person doesn't get enough vitaminD and calcium (from their diet and/or from supplements)
- insulin medication and a special diet may help someone with diabetes caused by cystic fibrosis control their blood sugar levels
13 February 2023
Help us improve NHS inform
Feedback Alert Title