[Spontaneous pneumomediastinum: asthma].

Pneumomediastinum is defined as the presence of free air in the mediastinum, and the spontaneous occurs in the absence of diseases or precipitating factors. It is rare in adults, and it is more frequent in newborns. However, it occurs more in young adults, with an 8:1 relationship between men and women. It constitutes a rare finding in asthma, representing 1% of the cases. More frequent symptoms are chest pain and dyspnea. Diagnosis is made with image examinations, such as radiography and chest computed tomography. Treatment of choice is conservative, nonoperative, with a favourable prognosis in the majority of the cases. Our aim is to report a case of this pathology in a young adult seen in our service with chest pain and dyspnea. He underwent complementary examinations and the diagnosis was spontaneous pneumo- mediastinum. This patient was submitted to a conservative treatment with excellent clinical evolution. At the moment, he is asymptomatic and under routine clinical care.