Congenital lobar emphysema (CLE) Parent Guide

What is Congenital Lobar Emphysema?

The cause of congenital lobar emphysema (CLE) is unknown, and nothing you did or didn’t do in pregnancy caused it.

Congenital lobar emphysema is a rare congenital lung malformation (CLM) where part of one lung becomes overinflated because air can get in—but not out—of that area. This happens very early in development, probably before the 10th week of gestation, when the cartilage or structure of the bronchus (the main airway branch) doesn’t form normally. The airway can be too narrow, soft, or “floppy,” which acts like a one-way valve. Air enters the lobe during inhalation but becomes trapped during exhalation. As a result, that lobe expands too much and can press on the other lobes or nearby organs.

CLE most often affects a single lobe of the lung, most commonly the left upper lobe, but it can occur in any lobe.

How rare is it?

Congenital lung malformations, including CLE, are uncommon. Estimates for all lesions are 1 in 2,500 live births. Improving prenatal imaging means more and more cases are being diagnosed before birth.

What happens during a CLE pregnancy?

CLE can sometimes be seen on a prenatal ultrasound or fetal MRI as an area of overinflated, bright lung, but it can be difficult to distinguish from CPAM or CBA before birth (if there is no feeder vessel to a systemic artery this indicates it is unlikely to be a BPS).

Because CLE and CPAM can look very similar on ultrasound, the exact diagnosis is often only confirmed with a CT scan after the baby is born or after surgery.

If diagnosed prenatally, your medical team will track the lesion’s size and whether it’s pushing on other structures in the chest like the heart or diaphragm (mediastinal shift). You may have ultrasounds every few weeks to monitor growth and check that there are no signs of fetal distress. Sometimes a fetal MRI may be carried out during the pregnancy to get a more detailed picture of the CLE lesion, although this is not offered everywhere or for every case. Hydrops is very rare in CLE, but may occur if the affected lobe compresses the heart or healthy lung tissue. As with other lung malformations, most lesions grow until about 26-28 weeks, then stabilize or shrink as the chest and lungs continue to grow. 

As with other lung malformations, your team may calculate the CPAM Volume Ratio (CVR) to estimate the lesion’s size in proportion to your baby’s head. A CVR < 1.6 is generally considered lower risk, while a CVR > 1.6 may lead to closer monitoring. Most babies with CLE and a stable CVR do extremely well and don’t require any intervention before birth.

Who will be involved in my care?

Many different specialists will now be involved in you and your baby’s care. Depending on where you’re receiving prenatal care, you will be connected to a maternal-fetal medicine (MFM) specialist. This is a doctor who works with pregnant women and unborn babies during high risk and complicated pregnancies. The MFM should understand congenital lung malformations like CLE and will make sure you and your baby are properly cared for. A radiologist will take specialized images of your unborn baby during ultrasounds and interpret these findings. They will be looking for how large the CLE lesion is and whether it shows any characteristics that might change the course of management and treatment. They will also closely look for any signs that the CLE might be pushing on other organs, such as shifting the heart to the other side of your baby’s chest (mediastinal shift). Doctors will also look for hydrops, which is when fluid builds up in a body’s tissues or organs (such as the lungs, heart, or belly), although this is very rare with CLE. Closer to the third trimester you will then likely have a consultation with a pediatric surgeon to understand if they plan to operate, when this would be, and what an operation would look like. You may also ask for a consultation with a neonatologist (the specialist doctors who work in NICUs) to understand what will happen at birth if your baby is symptomatic. 

What happens after birth?

How your baby does after delivery determines next steps. Many babies with CLE are asymptomatic at birth, meaning they breathe normally, and can stay with their parents for routine newborn care. All babies get a chest X-ray a few hours after birth, even if they’re breathing normally. If your baby doesn’t have any symptoms, the next step after you go home will be a CT scan of the chest (usually when they’re a few months old) and a visit with the pediatric surgeon. The CT scan is important because it shows the location and detailed characteristics of your baby’s lung lesion. The surgeon will talk to you about whether they recommend surgery, and what that looks like. Other babies may be symptomatic at birth and need some help to breathe, especially if the overinflated lobe compresses the healthy lung. If your baby shows breathing difficulty, they will go to the NICU for close monitoring and support.

Management and treatment

There are two main paths for CLE management and treatment. Which one you choose depends on the specifics of your baby’s CLE, the advice of your medical team, where in the world you are located, and what you feel is best for your child.

1. Surgical removal (lobectomy)

   • Recommended if the overinflated lobe is causing symptoms, compressing healthy lung tissue, or leading to repeated infections.

   • The operation is usually thoracoscopic (minimally invasive) and done in infancy or early childhood. In rare cases where the CLE presents an emergency situation after the baby is born, open chest surgery (thoracotomy) with removal of the affected lobe may have to be performed.

   • After surgery, the remaining lung expands to fill the space, and most children have normal lung function and can live fully active lives.

2. Careful observation (“watchful waiting”)

   • If your baby is asymptomatic, many teams recommend close observation with scheduled check-ups and imaging.

   • If breathing problems, recurrent chest infections, or worsening overinflation develop, surgery may be advised at that time.