What is primary ciliary dyskinesia (PCD)?
Primary ciliary dyskinesia (PCD) is a rare, inherited, long-term condition that children are born with.
Children with PCD have a problem with mucus build-up, which leads to swelling of the airways and infections in the airways and the ears. Children with PCD have the condition all their lives.
- How does PCD affect the body?
- What causes PCD?
- Is there any way to prevent PCD?
- What are signs of PCD in children?
- How is PCD diagnosed?
The tubes inside our lungs (airways) contain glands that produce mucus. This helps trap dust and germs. The mucus is cleared by tiny hairs called cilia that line the airways in the lungs, nose and ears.
If your child has PCD, the cilia don’t work properly. This leads to a build-up of mucus causing swelling and infection in the lungs and ears.
Growing up with PCD
Fiona’s sons both have primary ciliary dyskinesia.
If your child has PCD, contact the PCD Family Support Group for support and information.
Complications of PCD
Half of people with PCD have ‘situs inversus’. This means the organs in their chest and tummy are on the opposite side of the body from usual. PCD can also cause hearing problems and infertility.
The sooner your child is diagnosed with PCD, the sooner they can be treated to prevent or delay lung damage and help improve the chance of a normal life span.
PCD is caused by problems with faulty genes. To date, over 40 different genes that cause PCD have been identified. Genes carry instructions (like code) for making proteins in cilia. They code for what cilia look like, how they work and how they move. A faulty gene means that cilia do not work normally. This means mucus in the body is not cleared properly.
No, there’s nothing that can be done to prevent PCD. But even though it cannot be prevented, early diagnosis and treatment can stop PCD from causing permanent lung damage.
Genetic testing for PCD
Because PCD is caused by a problem with the genes, there is a lot of research into genetic testing. At the moment, genetic testing will only pick up some forms of PCD. This is improving with more research, and it is thought that currently, about 80% of people with PCD can be diagnosed using genetic blood tests. New genes are being identified all the time.
Most people with PCD have symptoms from birth or early infancy. Three quarters of children with PCD have trouble breathing. These children will need oxygen for days or weeks after they are born.
Other signs of PCD are caused by the infection and swelling in their lungs and ears. Your child might have:
- a constant blocked or runny nose
- a constant wet cough, even when well
- hearing problems - this affects half of all children with PCD
- wheezing or shortness of breath
- clubbing - swelling in the ends of the fingers
Even though most babies have symptoms from birth, the diagnosis of PCD may not be made until much later. This is because PCD is difficult to diagnose. Your doctor may think that there is another explanation for your baby’s symptoms.
But it is important that your child is diagnosed as early as possible. Take a look at our information on going to your doctor to help you get the most out of your appointment.
If your GP, paediatrician or other specialist doctor thinks your child has PCD they will refer them to a specialist team. Your child will either be seen at a clinic or an expert may visit a centre nearer your home. They will do tests to confirm the diagnosis.
Diagnostic tests for PCD
A sample of the air your child breathes out will be tested. This is called a nasal nitric oxide (nasal NO) measurement.
If your child is old enough, they may be asked to hold their breath, but the test can be done during normal breathing too.
If the nasal NO test is low, more tests may need to be done to help confirm the diagnosis of PCD:
- A sample of cilia from your child’s nose will be collected. This is called a nasal brush biopsy or nasal brushing. This is done in a specialist centre. The sample will be looked at under a microscope to see the movement of cilia, or tiny hairs, on the surface of these cells.
- Genetic blood tests can pick up genes associated with PCD in many cases.
Other tests for children with suspected PCD
These give useful information and include:
- a test to see how well your child’s lungs work - a lung function test or spirometry
- a chest X-ray
- a computer tomography or CT scan
Your child may need a general anaesthetic so their lungs can be looked at with a small camera. This test is called a bronchoscopy. While it is performed, samples may be collected from your child’s airway using a small brush called a bronchoscopic brush - this test is called a bronchial biopsy.