Congenital Lobar Emphysema - Incidence, Types, Causes, Symptoms, Diagnosis, and Treatment

Introduction:

Congenital lobar emphysema, also known as congenital lobar overinflation, is a respiratory disorder that is caused due to abnormal formation of the bronchial cartilage. It is commonly seen in infants and young children. Congenital lobar emphysema is often associated with heart disease. In this condition, the air enters the lungs but cannot vent out, resulting in enlarged or overinflated lung lobes. Most often, the exact cause of congenital lobar emphysema is idiopathic, and it may also be due to genetic conditions. The prenatal diagnosis of this condition is vital to relieve the baby from respiratory distress. Congenital lobar emphysema is reversible if diagnosed early.

What Are the Other Names of Congenital Lobar Emphysema (CLE)?

• Congenital pulmonary emphysema.

• Localized congenital emphysema.

• Lobar infantile emphysema.

• Lobar tension emphysema in infancy.

What Is the Incidence of CLE?

• It is seen in one in 20,000 to 30,000 live births with normal life expectancy.

• The white population is more commonly affected than the Blacks.

• Males are affected more than females in a ratio of 3:1.

• The upper left lobe of the lung is mainly affected and comprises 43 % of the total cases. The right middle lobe is involved in 32 %, and 21 % of the cases affect the right upper lobe. The lower lobes are rarely affected.

• 20 % of the cases are always associated with cardiac problems.

• Genetic predisposition in the family can increase the risk of congenital lobar emphysema.

What Are the Types of Congenital Lobar Emphysema?

Congenital lobar emphysema is classified into two types. They are:

1. Intrinsic Congenital Lobar Emphysema: It is caused due to obstruction within the lungs, conditions like abnormal bronchial cartilage, abnormal airways, etc.

2. Extrinsic Congenital Lobar Emphysema: It is due to the airway compressions arising from associated structures, cysts, etc., and creating pressure on the airways.

What Causes Congenital Emphysema in an Individual?

In almost 50 % of the cases of congenital lobar emphysema, the exact cause is still unknown. In about 25 % of the cases, there are developmental defects, hypoplasia, dysplasia of the lungs, and absence of bronchial cartilage. It results in air entrapment and bronchial collapse during expiration. Some cases are also associated with the autosomal dominant condition.

Autosomal Dominant Pattern of Inheritance: In an autosomal dominant condition, a single mutated gene is enough to cause the defect. It can be inherited from either of the parents or due to new mutations in the baby. In an autosomal dominant inheritance pattern, there is a 50 % chance of having an affected baby, irrespective of gender.

Other Conditions That Are Known to Cause CLE:

Parenchymal Diseases: Such as pulmonary alveolar glycogenesis, polyalveolar lobe, etc.

External Bronchial Obstruction:

• Pulmonary artery sling anomalies.

• Pulmonary rotation anomaly.

• Bronchogenic cysts, mediastinal masses.

• Lymphadenopathy.

• Duplication of the esophagus.

Internal Bronchial Obstruction:

• Meconium aspiration.

• Hypertrophic mucus membrane.

• Bronchial polyps.

• Foreign body aspiration.

• Mold mucus plaques.

What Are the Signs and Symptoms?

Most cases are symptomatic at birth and show signs of respiratory distress. The other 50 % of the cases show symptoms within six months of life. However, the most common clinical presentations are:

• Persistent cough.

• Respiratory distress with rapid breathing.

• Recurrent respiratory infections.

• Enlarged and overinflated lungs.

• Wheezing and rhonchi (whistling sounds heard while breathing).

• Bluish discoloration of the skin due to inadequate oxygen supply.

• Cardiac problems.

• On auscultation, abnormal breathing sounds may be encountered in the affected area.

• The symptoms get worse, leading to respiratory failure.

What Are the Possible Complications?

Cardiac Malformations:

• Patent ductus arteriosus.

• Septal defects.

• Tetralogy of Fallot.

Renal Problems:

• Aplastic kidneys.

• Horseshoe kidney.

Gastrointestinal Problems:

• Omphalocele.

• Pyloric stenosis.

Other Complications:

• Infantile death.

• Respiratory failure.

• Cyanosis.

• Diaphragmatic hernia.

What Are the Syndromes Associated With Congenital Lobar Emphysema?

• Williams-Beuren syndrome.

• Miller-Dieker syndrome.

• Niemann-Pick disease.

• Fanconi aplastic anemia.

What Are the Other Similar Conditions?

Congenital lobar emphysema is often misdiagnosed as other lung problems, such as:

• Congenital Adenomatoid Malformations: Type III adenomatoid condition and congenital lobar emphysema have similar features on ultrasound examination. But the only feature that differentiates CLE from adenomatoid cysts is the absence of cystic lesions in congenital lobar emphysema.

• Pneumonia: In pneumonia, there is an absence of hyperinflation in the affected lungs. In contrast, there is overinflation of the affected lungs in congenital lobar emphysema.

• Tension Pneumonia: The X-ray findings of tension pneumothorax show a depressed hemidiaphragm, which is absent in congenital lobar emphysema.

• Congenital Diaphragmatic Hernia: The clinical presentation of congenital diaphragmatic hernia and congenital lobar emphysema is almost similar, but no gas-filled bowels are seen in the chest in congenital lobar emphysema.

• Bronchial Asthma: A lung disease where the airways get inflamed, resulting in respiratory problems.

What Is the Prognosis?

• In mild to moderate cases, it has good results for non-surgical interventions.

• Surgery is indicated in severe cases of congenital lobar emphysema and has an excellent prognosis.

Is There Any Prevention?

As it is a congenital developmental disorder, it cannot be prevented. However, early diagnosis can reduce serious complications.

How to Diagnose Congenital Lobar Emphysema?

Congenital lobar emphysema can be diagnosed prenatally or soon after birth. The diagnostic procedures followed are:

• Prenatal Ultrasound: The affected lungs appear as hyperechoic mass with decreased blood supply with a mediastinal shift towards the opposite direction. There are also increased amniotic fluid levels (polyhydramnios).

• Magnetic Resonance Imaging: It is also performed to confirm the diagnosis and is a relatively safer procedure during pregnancy.

• Chest X-Ray: It is the first diagnostic procedure performed immediately after birth in infants with respiratory distress. It shows overinflation and hyperlucency of the affected lobes. The trachea and the mediastinum also shift to the opposite side.

• Pediatric Chest Computed Tomography (CT): The CT of the chest is performed in combination with single-photon emission tomography. A contrast medium is used to assess the vasculature and abnormalities. It also detects the need for lobectomy procedures.

• Lung Function Test: It is performed to assess the functional abilities of the lungs.

What Is the Treatment of Congenital Lobar Emphysema?

The treatment depends on the severity of the condition. In mild to moderate cases, it is treated by non-surgical interventions. And in severe cases, surgery is performed to improve the breathing of the patient.

• Lobectomy: It is a gold standard procedure for congenital lobar emphysema. The affected portion of the lungs is resected or surgically removed. In addition, it improves respiratory distress in the child.

Conclusion:

Despite being a rare condition, the prognosis is generally good to excellent. So the parents need not panic about the health of the child. With the advancements in medical and surgical techniques, the survival of the patient is increased. These children do well in their life as normal children. It might be a little distressing to hear about the medical condition of the child. Parents are given psychological counseling, and the child's medical condition is explained to them in detail. Regular long-term follow-ups are essential to assess the growth and health of the child.