Airway, Breathing and Lung Conditions

Congenital Lung Malformations

What Are Congenital Lung Malformations?

The name "congenital lung malformations" covers a broad range of lung problems. Some are cysts (abnormal closed sacs inside the body that contain fluid or gas). Some are solid. Some are mixed (part cyst, part solid). Lung problems that are congenital (present at birth) form while a baby's lungs are developing in the womb.

Two types of congenital lung malformations are:

  • Congenital cystic adenomatoid (pronounced add-en-OH-muh-toyd) malformations (CCAMs): These form when some of a baby's lung tissue grows more than it should. The growth may cause cysts filled with fluid, and it may cause solid masses. CCAMs may prevent some of the tiny air sacs (alveoli) in the lungs from developing normally. A baby may have only one CCAM or more than one. Most babies with CCAMs have them in only one section (lobe) of a lung. (CCAMs are also called congenital pulmonary adenomatoid malformations, or CPAMs.)
  • Pulmonary sequestrations (pronounced PULL-muh-nair-ee see-ques-TRAY-shuns) (PSs): These are solid masses of lung tissue. Usually they are closed off from the rest of the lung. They don't connect to the normal airways or to the normal blood supply for the lungs. They may be inside the lungs (intralobular) or outside the lungs (extralobular) in the chest or belly. (PSs are also called bronchopulmonary sequestrations, or BPSs.)

CCAMs and PSs are similar in the way they form. You can think of them as two ends of a spectrum. Some children have cysts or masses that seem to be somewhere between the two.

Another congenital lung problem sometimes grouped with lung cysts is congenital lobular emphysema (pronounced em-fizz-EE-muh). In this condition, the airway to one lobe of the lung is blocked. Air becomes trapped in this lobe, which makes it expand. It may expand so much that it presses on the healthy lobes or the other lung.

Congenital Lung Malformations in Children

The effects of congenital lung malformations depend on where they are and how large they are. Their location and size determine whether they will affect how the lungs and other nearby structures develop or work.

Some lung malformations, mainly small ones, have no effects at all. They may be found for the first time later in life when your child has an X-ray for some other reason.

Other lung malformations have such serious effects that they threaten the life of a baby even before birth. They may need to be treated while the baby is still in the womb.

One main concern is that a large malformation takes up space in your baby's chest. It may keep the lung on the same side from reaching a normal size (pulmonary hypoplasia). It may even push on the lung on the other side or on structures in the space between the lungs (mediastinum). These structures include the airways, the heart and the swallowing tube to the stomach (esophagus).

Another main concern is that your baby may have problems with blood flow. Pressure from CCAMs or PSs may restrict blood flow through the main vessel that carries blood from the lower body to the heart (vena cava). In some malformations, problems may also occur because of abnormal vessels to and from the mass. Problems with blood flow may lead to congenital heart failure (hydrops). Hydrops can be fatal for a baby.

Lung malformations can also cause extra amniotic fluid to build up around the baby inside the womb. This condition is called polyhydramnios (pronounced pahl-ee-hi-DRAM-nee-us).

Some babies with PSs have other birth defects, such as congenital diaphragmatic hernia or tracheoesophageal fistula.

Congenital Lung Malformations at Seattle Children's

We have treated many children with congenital lung malformations at Seattle Children's. We have the expertise to monitor babies with malformations that are found before birth and to provide prenatal treatment. Our physicians are experienced in performing the surgeries these babies need to remove CCAMs or PSs after birth. For patients with severe breathing problems, we have an Extracorporeal Life Support Program. Our Surgery Pulmonary Follow-Up Clinic helps your child be as healthy as possible after surgery.

When you come to Seattle Children's, you have a team of people to care for your child. Along with your child's surgeon, you are connected with nurses, dietitians, child life specialists and others. We work together to meet all of your child's health needs and help your family through this experience.

Since 1907, Seattle Children's has been treating children only. Our team members are trained in their fields and also in meeting the unique needs of children. For example, the doctors who give your child anesthesia are board certified in pediatric anesthesiology. This means they have extra years of training in how to take care of kids. Our child life specialists know how to help children understand their illnesses and treatments in ways that make sense for their age. Our expertise in pediatrics truly makes a difference for our patients and families.