Pulmonary Sequestration

Pulmonary sequestration is when you have lung tissue that’s not connected to your respiratory system. This means it doesn’t function as part of your lungs. You’re born with it (congenital), but many people aren’t diagnosed until they’re adults. Pregnancy care providers can also diagnose it on a prenatal ultrasound.

Pulmonary sequestration is most commonly found in the lower left lobe of your lungs. Sequestered tissue doesn’t get its blood supply from your pulmonary artery, as the rest of your lungs do. It’s attached to your thoracic or abdominal artery. This makes it different from congenital pulmonary airway malformation (CPAM), which gets its blood supply from your lungs.

Types

There are two types of pulmonary sequestration:

• Intralobar sequestration: This is when the tissue is contained inside your lungs, but it’s not connected to the rest of your lungs and airways. It’s the most common type.
• Extralobular sequestration: This is when the lung tissue is a mass separate from your lungs, in its own lining (pleura).

Symptoms of pulmonary sequestration

Many people don’t have noticeable symptoms of pulmonary sequestration. If you or your child do have symptoms, they could include:

• Chronic cough
• Wheezing
• Shortness of breath
• Frequent lung infections (pneumonia)
• Coughing up blood (rare)

It might also cause a baby to have difficulty breathing at birth.

Pulmonary sequestration causes

Pulmonary sequestration happens before birth, while a fetus is still developing. Experts aren’t sure what causes the extra tissue to grow. There’s no gene change known to cause it and it doesn’t seem to run in families.

Complications

If a mass of lung tissue is too large in a fetus, it can cause:

• Fluid around the lungs (pleural effusion)
• Fluid buildup (hydrops fetalis)
• Underdeveloped lungs
• Heart failure

In adults, the most common complications are coughing up blood and frequent lung infections.

How doctors diagnose pulmonary sequestration

Your pregnancy care provider might diagnose pulmonary sequestration during a prenatal ultrasound. In babies, kids and adults, providers use a CT angiogram (a type of medical imaging) to diagnose it. Sometimes, a provider might see it on imaging that was taken for other reasons.

How is pulmonary sequestration treated?

A surgeon removes the extra lung tissue to treat sequestration. Small areas of tissue outside your lungs that aren’t causing symptoms don’t usually need treatment. You or your child may need surgery to remove the tissue if it:

• Is large
• Is causing symptoms or repeated infections
• Will interfere with the development of your child’s organs

In most cases, it’s safe to wait until your child is 6 to 12 months old to get surgery. If there’s excess fluid or other complications, your baby may need surgery immediately after a C-section delivery. Or your provider may need to use a shunt to drain fluid for the rest of your pregnancy until you can deliver.

When should I see my healthcare provider?

Talk to a healthcare provider if you or your child has a long-lasting cough or wheezing. Getting sick frequently with serious lung infections is also a reason to see a provider and get to the bottom of things.

What can I expect if my child has pulmonary sequestration?

Most cases of pulmonary sequestration have an excellent outlook (prognosis). If it’s diagnosed during pregnancy, your provider will monitor you closely for complications. After surgery, most kids’ lungs are able to grow as they typically would. They’ll have to have regular doctor visits for about a year to check in on their health.

Complications like pleural effusion can impact your child’s prognosis. They may need monitoring throughout childhood or other special care.

What can I expect if I have pulmonary sequestration?

If you have pulmonary sequestration that was discovered as an adult, excess lung tissue won’t grow larger. In fact, it usually gets smaller before birth. If the tissue hasn’t been causing symptoms or complications, your provider probably won’t recommend treatment.