Chapter 405 Pneumothorax
Pneumothorax is the accumulation of extrapulmonary air within the chest, most commonly from leakage of air from within the lung. Air leaks can be primary or secondary and can be spontaneous, traumatic, iatrogenic, or catamenial (Table 405-1). Pneumothorax in the neonatal period is also discussed in Chapter 95.12.
Table 405-1 CAUSES OF PNEUMOTHORAX IN CHILDREN
SPONTANEOUS
TRAUMATIC
* Associated with renal agenesis, diaphragmatic hernia, amniotic fluid leaks.
From Kuhn JP, Slovis TL, Haller JO: Caffey’s pediatric diagnostic imaging, vol 1, ed 10, Philadelphia, 2004, Mosby.
Etiology and Epidemiology
A primary spontaneous pneumothorax occurs without trauma or underlying lung disease. Spontaneous pneumothorax with or without exertion occurs occasionally in teenagers and young adults, most frequently in males who are tall, thin, and thought to have subpleural blebs. Familial cases of spontaneous pneumothorax occur and have been associated with mutations in the folliculin gene. Patients with collagen synthesis defects, such as Ehlers-Danlos disease (Chapter 651) and Marfan syndrome (Chapter 693) are unusually prone to the development of pneumothorax.
A pneumothorax arising as a complication of an underlying lung disorder but without trauma is a secondary spontaneous pneumothorax. Pneumothorax can occur in pneumonia, usually with empyema; it can also be secondary to pulmonary abscess, gangrene, infarct, rupture of a cyst or an emphysematous bleb (in asthma), or foreign bodies in the lung. In infants with staphylococcal pneumonia, the incidence of pneumothorax is relatively high. It is found in ≈5% of hospitalized asthmatic children and usually resolves without treatment. Pneumothorax is a serious complication in cystic fibrosis (CF; Chapter 395). Pneumothorax also occurs in patients with lymphoma or other malignancies, and in graft versus host disease with bronchiolitis obliterans.
