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.

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:

People with the condition can also develop a number of related conditions, including diabetes (in adulthood), thin, weakened bones (osteoporosis) and liver problems.

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 per cent chance that each child they have will be born with 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. This is then tested for abnormalities that could indicate cystic fibrosis.

More tests will be needed to confirm the diagnosis. Any baby with a positive result will be referred to specialist services in the hospital.

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.

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

Treatments for cystic fibrosis 

There's currently no cure for cystic fibrosis. However, it's possible to help control the symptoms and delay 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.

The RBHSC Cystic Fibrosis (CF) unit is the regional centre for the care of all children with cystic fibrosis in Northern Ireland. The Adult Cystic Fibrosis (CF) unit is a regional service based at Belfast City Hospital.

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 make it easier to absorb food
  • following a special diet and taking supplements to prevent malnutrition

Treatment may eventually involve a lung transplant, if the lungs become damaged by infection and inflammation.

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. This is 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 41. Children born with the condition nowadays are likely to live longer than this.

The information on this page has been adapted from original content from the NHS website.

For further information see terms and conditions.

This page was reviewed November 2017

This page is due for review April 2019

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