Pneumomediastinum, subcutaneous emphysema and pneumorrhachis in asthmatic children.

Pneumomediastinum (PM), subcutaneous emphysema (SE) and pneumorrhachis (also known as epidural air (EDA) or epidural emphysema) are very rare findings in children. PM is defined as the passage of air from intra-alveolar space to interstitium and, later, to the mediastinum. From the mediastinum, the air may catch up subcutaneous tissue (usually of the neck) and/or epidural space via the cervical fascial planes and neural foramina, forming respectively SE and EDA. The PM can be divided in spontaneous (or idiopathic) and secondary PM. Only few studies have evaluated the exact incidence of PM and its complications in children, and to define the correct diagnostic work up, treatment and outpatient follow-up. We report the case of a 9-year-old child with undiagnosed asthma that, during severe asthmatic flare secondary to acute infection of high airway, developed PM, SE and EDA.