Cystic fibrosis

Cystic fibrosis is an inherited condition. Thick, sticky mucus can build up and clog the lungs and the digestive system.

Breathing and digestion problems can start from a young age. Over many years the lungs get more and more damaged, and they may eventually stop working properly.

It's estimated that 1 in every 2,500 babies born in the UK has cystic fibrosis.

Several treatments can help reduce the problems the condition causes. Sadly, people with cystic fibrosis still have a shorter life expectancy on average.

Symptoms of cystic fibrosis usually start in early childhood. Sometimes they appear very soon after birth, and in other cases they may not be obvious until adulthood.

Some of the main symptoms can include:

• recurring chest infections
• difficulty putting on weight
• frequent, wet-sounding coughs
• diarrhoea
• occasional wheezing and shortness of breath

People with cystic fibrosis can also develop a number of related conditions, including diabetes, thin, weakened bones (osteoporosis) and liver problems.

Cystic fibrosis is caused by a faulty gene, and a child inherits it from both parents.

This faulty gene makes it hard for some cells to move salt and water across the cell wall. Along with repeated infections, that can lead to thick, sticky mucus building up in the body's tubes and passageways.

For a child to be born with cystic fibrosis, they must inherit two copies of the faulty gene, one from each parent. The parents usually don't have the condition themselves, because each of them carries only 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.

There's no cure for cystic fibrosis at the moment. But several treatments can help control the symptoms, prevent complications and make the condition easier to live with.

Treatment can 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

If the lungs become greatly damaged, a lung transplant may eventually be needed.

Cystic fibrosis is a progressive condition, which means it tends to get worse over time. In the end it can be fatal, if it leads to a serious infection or the lungs stop working properly.

The outlook has improved a great deal in recent years because treatment has advanced. Even so, most people with cystic fibrosis will have a shorter-than-average life expectancy. At present, about half of the people with the condition will live past the age of 40. Children born with it today are likely to live longer than this.

Cystic fibrosis can cause a number of different problems, but the lungs and the digestive system are the two main areas it affects.

Symptoms usually start in early childhood. Sometimes they show up soon after birth, and very occasionally they aren't obvious until adulthood.

These days, cystic fibrosis is usually diagnosed before any symptoms appear, through screening tests done soon after birth.

The main problems linked to cystic fibrosis are outlined below.

In cystic fibrosis, sticky mucus can clog the lungs and airways. This can lead to several problems:

• recurring chest infections, which happen because the mucus in the lungs is an ideal breeding ground for bacteria
• persistent inflammation of the airways, which can make them abnormally widened (bronchiectasis)
• increased coughing
• occasional wheezing and shortness of breath

Over time, the lungs can become more and more damaged, and they may eventually stop working properly.

In cystic fibrosis, the thick mucus can also block parts of the digestive system. That changes how food moves 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), which often needs an operation to remove the blockage
• jaundice
• diarrhoea or large, smelly stools
• problems putting on weight and growing, which can happen because the body struggles to digest and absorb nutrients (malnutrition)
• diabetes from late childhood or early adulthood, which can develop if the pancreas becomes severely damaged

People with cystic fibrosis can also run into a number of other problems, including:

• sinusitis
• nasal polyps
• thin, weakened bones (osteoporosis), which can happen because of repeated infections, poor growth, lack of physical activity and malnutrition
• swelling and pain in the joints (arthritis or arthralgia) from late childhood
• difficulty having children. Most men with cystic fibrosis can't have children naturally because the tubes that carry sperm don't develop correctly (although some fertility treatments may still work). 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)

Cystic fibrosis is caused by a faulty gene, and a child gets it from both parents.

Because of this gene, some cells have trouble moving salt and water across the cell wall. That problem, together with repeated infections, can lead to thick, sticky mucus building up in the body's tubes and passageways, especially in the lungs and the digestive system.

A child is born with cystic fibrosis. You can't catch it from someone who has it.

Genes come in pairs. You inherit one set from your mother and the other from your father.

For a child to be born with cystic fibrosis, they have to inherit a copy of the faulty gene from both parents.

This can happen when the parents are 'carriers' of the faulty gene. A carrier doesn'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

Doctors call this an autosomal recessive inheritance pattern.

Cystic fibrosis can be diagnosed with tests at any age. Today, most cases are picked up soon after birth through newborn screening. But if an older child or an adult has symptoms of cystic fibrosis and wasn't screened, they can still have tests to check for it.

Some people may also be advised to have a test to find out whether they are a "carrier" of the faulty gene that causes cystic fibrosis.

In the newborn blood spot test, a health professional pricks your baby's heel when they are five to eight days old and collects drops of blood on a special card. The blood goes to a laboratory, where it is checked for abnormalities that could point to cystic fibrosis.

You should get the results by the time your baby is six to eight weeks old. If a problem is found, you'll be contacted sooner and asked to come to a hospital appointment.

The screening result isn't 100% accurate, so more tests will be done 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.

Doctors carry out tests to confirm cystic fibrosis if screening suggests your child may have it. They do the same if your doctor thinks you could have the condition and you haven't been screened before.

Two main tests can be used to diagnose cystic fibrosis:

• sweat test, which measures the amount of salt in sweat, because 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 the one used most often. Genetic testing may be done if the sweat test result is inconclusive, or to identify the specific genetic fault that's causing the condition.

A test to find out if you carry the faulty gene that causes cystic fibrosis can be useful in a few situations:

• 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

The test is usually a blood test, or occasionally a special mouthwash that collects a sample of cells. The sample goes to a laboratory, where it's checked for the faulty gene.

Knowing if you're a carrier can help show if you're at risk of having a child with cystic fibrosis. A genetic counsellor will explain the results to you and talk through what they mean and the options open to you in future pregnancies.

There's no cure for cystic fibrosis at the moment. But it is 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 looked after by a team of healthcare professionals at a specialist cystic fibrosis centre. The team will draw up a care plan that's tailored to that person's individual needs.

Several different 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 several different medicines to treat and prevent lung problems. These may be swallowed, inhaled or injected.

Some of the main medicines 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, though 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 the condition are up to date with all routine vaccinations, and that they have the flu jab each year once they're old enough.

Alongside medicine, people with cystic fibrosis can use special techniques to help keep the lungs and airways clear. A physiotherapist can give you advice.

Some of the main techniques are:

• active cycle of breathing techniques (ACBT), which is a sequence of relaxed breathing, followed by deep breathing exercises and then huffing
• autogenic drainage, which is a series of gentle breathing techniques that clear mucus from the lungs
• modified postural drainage, where you change your position to make it easier to remove mucus from your lungs
• airway clearance devices, which are 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 to £60 for one of these)

Your care team can tell you more about any of these techniques.

For people with cystic fibrosis, good nutrition matters a great deal. It helps them grow and develop normally, and it keeps them from falling ill again and again.

The difficulty is that most people with cystic fibrosis can't digest food or absorb nutrients properly, and this starts from babyhood. Sometimes the condition damages the pancreas over time, and that causes the same problem.

A dietitian will tell you what you can do to help avoid malnutrition. They may recommend:

• taking digestive enzyme capsules with all meals and snacks to help with digestion, and 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

If you have severe cystic fibrosis, your lungs may stop working properly and every medical treatment may have failed to help. In that case, a lung transplant may be recommended.

A lung transplant is a serious operation and it carries risks. But it can greatly improve both the length and the quality of life for people with severe cystic fibrosis.

The outlook for people with cystic fibrosis is often better than for many other transplant patients, because 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 other problems too, and some of these may improve with treatment. For example:

• exercise can help keep bones and joints healthy, and it's recommended for everyone with cystic fibrosis. Any sport or exercise is usually good, but if you're not sure about a particular activity, ask your physiotherapist for advice
• medicines called bisphosphonates can help treat weak and brittle bones, which may happen as a result of cystic fibrosis if the person doesn't get enough vitamin D and calcium (from their diet and/or from supplements)
• insulin medicine and a special diet may help someone with diabetes caused by cystic fibrosis control their blood sugar levels