Congenital pulmonary airway malformation (CPAM)

Congenital lung malformations (CLMs) is the name for a group of lung problems that a baby may be born with. They happen when your baby’s lungs do not grow properly in the womb.

Most babies with a CLM do not have symptoms when they’re young and can grow up to be healthy children.

There are lots of different types of CLM. The type of CLM your baby has depends on:

• the parts of the lungs that are affected. There can be a problem with the lung tissue, airways, or multiple parts of the lungs.
• what the malformation is or how the lungs have grown differently.

How common are congenital lung malformations?

Congenital lung malformations are rare. Around 4 in every 10,000 babies are born with a CLM.

Congenital pulmonary airway malformations (CPAMs) are the most common type of CLM. 1 in 10,000 babies are born with a CPAM.

CPAMs are spaces filled with air or liquid that grow in your baby’s airways or lungs when they’re in the womb. These are called cysts. The area with the cyst does not work like healthy lung tissue, but the rest of your baby’s lungs usually grow healthily. CPAM cysts can get smaller and sometimes completely disappear during pregnancy.

Like other CLMs, there are also different types of CPAM. The type of CPAM depends on where and what the malformation is, for example how big the cysts are. This also means that if your child has CPAM, their symptoms depend on what type they have.

We do not know exactly what causes CLMs like CPAM yet. Researchers are working to understand more about CLMs and how they happen.

We still need more research to explore this, but CLMs might be linked to:

• genetics. Some CLMs might happen when the baby’s genes send the wrong messages, which means their lungs do not develop properly in the womb.
• being exposed to risks during pregnancy, like high levels of air pollution or passive smoking, can make a baby more likely to be born with a CLM.
• other congenital malformations. Some babies born with heart or blood vessel malformations may also be born with CLMs.

Most CLMs, including CPAM, will be found during routine scans before your baby is born, especially at the 20-week scan.

If a healthcare professional thinks your unborn baby might have a CLM, they will refer you to a specialist doctor.

Healthcare professionals cannot be sure which CLM your baby has until they’re born. But spotting a possible CLM during pregnancy will help you and your healthcare professionals plan your birth and the treatment your baby may need after they are born.

What happens next if my healthcare professional thinks my baby has a CLM?

Talk to your healthcare professional about what follow-up tests you’ll be offered before and after your baby is born because this is different for everyone.

During pregnancy

You will be offered extra follow-up scans to check your baby’s lung health as they grow. These may be more ultrasound scans or MRI (Magnetic Resonance Imaging) scans.

Find out more about what happens if an antenatal screening test finds something, including what tests you may be offered, from the NHS website.

Some CLMs become smaller during pregnancy. Most babies with potential CLMs do not need treatment before they’re born and they’re born without complications.

In very rare and serious cases, babies might have treatment before they’re born. This is called antenatal treatment. Healthcare professionals will only suggest this if it’ll give your baby the best chance of being born safely.

In rare cases, CLMs can sometimes increase the risk of heart failure before your baby is born. Sadly, your baby’s chances of survival are very low when this happens. The charity Tommy’s have information and support for anyone who has experienced the loss of a baby.

Find out more about tests during pregnancy from Antenatal Results & Choices (ARC).

After your baby is born

A specialist doctor will check your baby’s breathing and might do some tests like a chest X-ray.

If your baby is born with serious breathing problems, they may need help to breathe straight away. They might be admitted to a specialist hospital unit and put on a breathing machine called a ventilator to make sure they get enough oxygen.

Your baby is likely to have a computerised tomography (CT) scan before they’re six months old to check what CLM they have. Some babies may have an MRI scan. These tests help healthcare professionals to find out more about your baby’s CLM so that they can plan the best treatment.

Can adults be diagnosed with CLMs?

You can be diagnosed with a CLM as an adult, but this is less common than being diagnosed as a child.

You’re more likely to be diagnosed as an adult if you only start getting symptoms when you’re older.

In some cases, healthcare professionals might find a CLM when you’re having other lung scans.

Your baby’s treatment will depend on their type of CLM and what symptoms they have.

Babies and children with CLMs will be seen by specialist healthcare professionals to find out more about their condition. They will check your child’s breathing and look at their lungs on a CT scan or an MRI scan.

Specialists will support you to decide the best treatment plan to help your child manage their condition.

It’s important to speak to your child’s healthcare professionals for specific advice. This is because there are lots of types of CLMs and they can affect people differently.

If your child does not have symptoms (asymptomatic)

If your child does not have symptoms at birth, they might not need treatment straight away.

Talk to your child’s healthcare professionals about the treatment options available and what they recommend for your child. Make sure you know what to do if your child starts to get symptoms and who to call if you need extra support.

There are different ways to manage asymptomatic CLMs:

• Regular check-ups. Some healthcare professionals will suggest regular CT scans and check-ups to monitor your child’s condition. This is helpful to check if the CLM is staying the same or changing in any way, for example getting bigger.
• Surgery. In some cases, healthcare professionals may offer surgery to remove the CLM before your child has any symptoms. This is usually to try to avoid the risk of your child developing symptoms or other complications from the CLM when they get older.

If a healthcare professional suggests surgery, you should be involved in making this decision.  Ask your paediatrician to explain the risks and benefits of surgery.

The long-term outlook for CLMs depends on the type of condition your child has and how serious it is.

Children that are diagnosed with a CLM before birth or when they’re young have a good chance of living a healthy life. This is because getting an early diagnosis means that children will have regular check-ups, so healthcare professionals can monitor their condition and adapt their treatment plan if needed.

Most people live with a CLM without it affecting their ability to do daily activities.

Complications from congenital lung malformations

Some people experience complications from their CLMs. It’s difficult to know exactly why, but complications are more likely to happen if the CLM is very serious, or it’s diagnosed later in life.

The most common complication of CLMs in older children and adults that do not have symptoms when they’re young is getting lung infections that keep coming back, like pneumonia.

About 3 in 100 people that have not had surgery for their CLM may get other complications. These include:

• collapsed lung, called pneumothorax
• bleeding in the lungs or lung lining
• heart failure
• lung cancer, or cancer in other parts of the body.

Talk to your child’s healthcare professionals if you have any questions or worries about their condition.