Spontaneous pneumomediastinum in children.

SUMMARY. Spontaneous pneumomediastinum (SPM) is rare in children, mainly affecting male adolescents. It is usually secondary to alveolar rupture in the pulmonary interstitium, followed by dissection of gas towards the hilum and mediastinum. Many pathological and physiological events can lead to alveolar rupture, but the most common cause in children is asthma. The clinical diagnosis is based on the symptom triad of chest pain, dyspnea, and subcutaneous emphysema, and is also based on Hamman's sign. The diagnosis is confirmed by chest radiography. The main differential diagnosis is esophageal perforation, which requires an esophagogram with contrast when there is the slightest doubt in the diagnosis. Spontaneous pneumomediastinum generally resolves spontaneously within a few days, meaning that ambulatory treatment is usually appropriate. Management consists of treating the underlying cause (if identified), rest, analgesics, and simple clinical monitoring. Predisposing factors should be identified and controlled to prevent recurrence. Cases of idiopathic SPM necessitate diagnostic pulmonary function tests after the acute episode, to establish whether the child has asthma.