Congenital lobar pulmonary emphysema mimicking contralateral pulmonary hypoplasia

Background

Congenital lobar pulmonary emphysema (CLPE) is a rare condition, and it is characterized by overdistension of the affected lobe and compression and displacement of adjacent normal lung tissue and mediastinum.

Case

A 2-month-old boy was admitted to the ICU with respiratory failure. At admission, he presented with bilateral pneumonia and respiratory failure, requiring mechanical ventilation and antibiotics. Despite the initial treatment, he persisted with desaturation and marked hypercapnia. Chest X-rays revealed hyperinflation of the left lung, with significant reduction of the right lung area. The first CT scan showed extensive consolidation of the right lung and atelectasis. Bronchoscopy revealed reduction of the right bronchus caliber and was diagnosed as right lung hypoplasia. The child continued to have desaturation and it was not possible to wean him off mechanical ventilation. Fifteen days later he had another CT scan showing overdistension of the left lung apex, suggesting the diagnosis of congenital lobar emphysema. After the second CT scan, we performed a selective intubation to the right, trying to inflate the collapsed right lung, and there was a marked improvement on saturation; a chest X-ray showed aeration of the right lung. The child was submitted to superior left lobe lobectomy, and after the surgery he improved in pulmonary function and it was possible to wean him off mechanical ventilation. The patient was discharged from the ICU 20 days later.

Discussion

CLPE is characterized by postnatal overdistension of one or more pulmonary lobes, the left lobe being the most frequently affected. One-half of the cases have unknown causes. When a marked overdistension is present, lung herniation and collapse of the contralateral lung can occur. In the first instance, we considered the hypothesis of right lung hypoplasia, following bronchoscopy findings. CLPE was confirmed after a second CT scan.

Conclusion

CLPE is a rare pulmonary condition, usually diagnosed before 6 months of age; it must be considered a differential diagnosis in cases of suspected contralateral lung hypoplasia.