Congenital Lobar Emphysema

What is Congenital Lobar Emphysema?

Congenital lung diseases are unusual but often quite unique in how they appear. They can range from large growths that need immediate surgery to smaller issues that don’t show any symptoms. Because these birth defects in the lung can have serious effects, it’s important for us to understand how to identify and treat these abnormal growths. The way the lungs develop and their structure are key to understanding these malformations and help us make sense of each individual disease.

Congenital lobar emphysema (CLE) is a rare lung defect that can vary greatly in how it appears, making it difficult to diagnose and treat. It’s often linked with high rates of illness and death. CLE is identified by breathing difficulties due to one or more sections of the lung, which are otherwise normal, becoming too expanded. This expansion doesn’t destroy the tiny air sacs in the lung, but it does squish the surrounding lung tissue. That’s why it’s also referred to as congenital lung overinflation. The problem here is that during the outbreath part of breathing, air gets trapped in the lung. Over time, this leads to repeated breathing difficulties. The bloated section of the lung, in effect, doesn’t work properly because it’s too expanded and filled with trapped air. CLE is often detected in newborns, but in some cases, it only becomes noticeable in adulthood. Thankfully, if it’s diagnosed and treated promptly, this disease can potentially be reversed.

What Causes Congenital Lobar Emphysema?

The cause of congenital lobar emphysema, a lung condition present from birth, remains unknown for about half of the patients. In 25% of patients, the problem lies in the cartilage of the bronchial tubes, which help air flow in and out of the lungs. When the cartilage is missing or not formed correctly, the bronchial tubes may collapse, trapping air in the lungs during breathing out.

Here are a few possible reasons why congenital lobar emphysema may occur:

• We don’t know the cause in 50% of cases.
• In 25% of patients, it’s due to missing or improperly formed bronchial cartilage.
• Diseases affecting the lung tissue itself.
• Obstruction of the bronchial tubes from either within (internal) or outside (external).

One theory suggests that this condition could be due to a lobe of the lung having too many air sacs (or alveoli). These “poly-alveolar” lobes could have 3 to 5 times the normal amount of air sacs compared to other lobes, but why this would trap air is not clear. Additionally, the disease could be due to problems within the bronchial tubes such as narrowing or weakness.

Finally, congenital lobar emphysema might also be caused by diseases originating from nearby structures like blood vessels or masses in the middle part of the chest (mediastinum).

Risk Factors and Frequency for Congenital Lobar Emphysema

Congenital lobar emphysema (CLE) is a condition that affects about 1 in 20,000 to 30,000 live births. It tends to affect males more than females, with a ratio of 3 to 1. The condition is more common in infants and very rarely seen in adults. About a third of babies with CLE show symptoms at birth, which usually leads to a diagnosis within the first six months. Different parts of the lung can be affected, with the left upper lobe being the most common.

• About 1 in 20,000 to 30,000 live births are affected by CLE.
• It occurs more frequently in males than females (a ratio of 3 to 1).
• CLE is most common in infants and very rare in adults.
• One-third of cases show symptoms at birth, leading to early diagnosis, usually within first six months.
• The left upper lobe of the lung is frequently affected (43% of cases), followed by the right middle lobe (32%) and right upper lobe (21%). The lower lobe involvement is rare (2% of cases).
• 25% of cases are due to a deformity of the bronchial cartilages, and another 25% because of obstruction of the bronchi.
• CLE can also be associated with issues in other body systems, particularly the heart in about 20% of cases.

Signs and Symptoms of Congenital Lobar Emphysema

Congenital lobar emphysema is a serious condition that can greatly affect a newborn baby’s ability to breathe and feed. About half of babies with this condition show symptoms right from birth, and the remaining usually start to show symptoms within the first six months. The most common symptoms include difficulty in feeding and breathing, wheezing, signs of struggling to breathe like chest retractions, and bluish skin or lips due to lack of oxygen. Often these babies have a history of ongoing cough and frequent respiratory infections. Because these symptoms occur in other illnesses too, some babies unfortunately get misdiagnosed with lung conditions like pneumonia or pneumothorax.

In babies with congenital lobar emphysema, certain parts of the lung called lobes are overly inflated which hampers proper ventilation and blood flow. As these overly inflated lobes continue to grow and take up more space, they compress the neighboring organs which further worsens the ventilation and blood flow imbalance, potentially leading to respiratory failure.

During a physical examination, doctors would note a baby’s wheezing and noisy breathing. By tapping on the chest, doctors can noticed that the affected lobe will have a different drum-like sound compared to the rest of the chest. Breath sounds when listened with a stethoscope would also be quieter in the affected area. It’s also worth mentioning that congenital lobar emphysema can sometimes occur alongside heart defects.

Testing for Congenital Lobar Emphysema

Congenital lobar emphysema causes certain parts of the lungs (lobes) to trap air and become overly inflated, despite having limited blood flow to these areas. Both pediatric and adult radiologists should understand the features of this condition to improve the accuracy of diagnosis. In some cases, congenital lobar emphysema can even be diagnosed before a baby is born: the unborn baby’s lungs may show increased brightness (hyper-echogenicity) on ultrasound, without any abnormalities in blood flow. Additionally, there could be too much amniotic fluid (polyhydramnios) or the heart and other organs could be pushed to one side (mediastinal shift). Using magnetic resonance imaging (MRI) is also safe to verify this diagnosis before birth.

In patients with breathing difficulties, a chest x-ray is usually the first step in diagnosis. The x-ray will reveal overinflation and increased brightness (hyperlucency) in the affected lung lobe if it is due to congenital lobar emphysema. However, a CT scan of the lungs is considered the best way to diagnose this condition. It helps scrutinize the affected lobe and adjacent structures, including blood vessels, especially when IV contrast is used.

In cases where removing the affected lobe (lobectomy) is being considered as treatment, a specific type of scan, called single-photon emission tomography combined with CT, can assess how well blood flow and air movement (perfusion and ventilation) are related in the affected lobes.

Lastly, always keep in mind that a high suspicion for congenital lobar emphysema can help in diagnosing patients who show up with symptoms.

Treatment Options for Congenital Lobar Emphysema

The severity of a patient’s health condition, known as congenital lobar emphysema, determines the appropriate form of treatment. While some patients show no symptoms, almost half of them start showing symptoms within the first month after birth. If the symptoms are mild or moderate, it may be possible to manage the condition with a less invasive approach, such as medication or lifestyle modifications.

However, in cases where symptoms are severe, surgery to remove a portion of the lung (a lobectomy) is often considered the best course of action. Yet, advances in medical technology are making non-surgical treatment options, often diagnosed before birth and managed accordingly, increasingly popular.

What else can Congenital Lobar Emphysema be?

When a baby is born with a condition called congenital lobar emphysema, there are other medical conditions that can look similar. These include:

• Congenital Cystic Adenomatoid Malformation: Both this condition and congenital lobar emphysema can appear as a bright mass on an ultrasound. However, unlike congenital cystic adenomatoid malformation, congenital lobar emphysema does not include cystic lesions.
• Pneumonia: This is a condition that can cause symptoms like fever, chest retraction, and bluish skin. The lung affected by pneumonia may show up on a chest X-ray as a collapsed consolidation, which improves after taking antibiotics. This is different from congenital lobar emphysema as the lung affected by emphysema is overly inflated, not collapsed.
• Tension Pneumothorax: Patients suffering from this condition can also experience breathing difficulties like those with congenital lobar emphysema. The physical exam can reveal overly loud resonance and decreased breathing sounds in the affected lung. The X-ray shows the heart and other central organs pushed to the opposite lung. This condition can cause low blood pressure and needs immediate medical attention. One way to distinguish it from congenital lobar emphysema is that in tension pneumothorax, the X-ray show signs of the diaphragm being pushed down, which does not occur in congenital lobar emphysema.
• Congenital Diaphragmatic Hernia: Both conditions will show an overly bright lung on a chest X-ray. But, congenital diaphragmatic hernia can be distinguished because the air fileld bowel loops are visible in the chest, a feature not associated with congenital lobar emphysema.

It’s crucial to distinguish between these conditions to ensure the correct treatment is given.

What to expect with Congenital Lobar Emphysema

In simpler and moderate cases, non-surgical treatment usually works well. For patients experiencing severe symptoms, removal of a section of the lung (lobectomy) has great outcomes, and death from this surgery is very low.

Possible Complications When Diagnosed with Congenital Lobar Emphysema

Congenital Lobar Emphysema can cause several complications. These include:

• Blue skin color due to lack of oxygen (Cyanosis)
• Difficulties with breathing (Respiratory failure)
• Problems arising from lung surgery (Surgical complications due to lobectomy)
• Death in infancy (Infantile death)

Preventing Congenital Lobar Emphysema

People diagnosed with congenital lobar emphysema can have varying symptoms. They can commonly experience breathing difficulties, a whistling noise when breathing, a bluish skin color due to lack of oxygen, and trouble with eating. It’s crucial to provide emotional support to the parents of the diagnosed child. They need thorough information about this condition, what to expect, potential treatments, the likelihood of recovery, and how it might affect daily life.

If the child does not show symptoms, parents should be guided on how to manage the situation. Regular check-ups and monitoring are necessary, and parents should know what steps to follow if symptoms start appearing.

If the child does show severe symptoms, parents should be informed about the potential need for surgery and the expected recovery process, as well as any necessary lifestyle changes. Education about the disease is crucial. Using visuals like flow charts, drawings, and videos can really help parents understand all aspects of the disease, its treatment, and required lifestyle adjustments. This way, parents will have the information they need and feel content that their child’s care is well-handled.