PNEUMATOCELE PNEUMONIA

A pneumatocele is a benign air-containing cyst in the lung most commonly the result of Staphylococcus Aureus pneumonia. Other less common bacteria associated are Hemophilus Influenza, Pseudomonas Aeruginosa and Strep Pneumonia. Pneumatoceles are most commonly seen in young children (almost 50% of cases are less than one-year of age) during the acute phase of the pneumonic process. In a low percentage of cases the pneumatocele can be the result of closed chest trauma. In the infectious pneumonic setting the inflammatory process causes necrosis and liquefaction of the lung parenchyma followed by air leak and subpleural dissection forming a thin-walled cyst. Fever and respiratory distress are the most common symptoms during initial presentation. Diagnosis is established with the help of simple chest-x-ray films. CT-Scan might be needed to differentiate between a congenital lung cyst or cystic adenomatoid malformation. Follow-up films will help determine if the pneumatocele is growing or not in size.

Rapidly enlarging pneumatocele may need percutaneous catheter decompression. Surgery is indicated only if the child develops respiratory distress or the pneumatocele ruptures into the pleural space creating a tension pneumothorax, a bronchopulmonary fistula or an empyema. Fortunately most pneumatoceles gradually decrease in size and disappear after the acute pulmonary infection subsides in a period that may range between six weeks and six months.