Persistent pneumomediastinum and dermatomyositis: a case report and review of the literature.

We describe a 42-year-old man with dermatomyositis and interstitial lung disease who presented with anterior neck pain and dyspnoea. Chest radiographs showed subcutaneous emphysema, pneumomediastinum and diffuse reticulonodular infiltration in both lungs. After the administration of high doses of prednisolone, an improvement of pulmonary function and respiratory symptoms was observed but the pneumomediastinum persists 12 months after diagnosis, and without any complication. We review the cases that have been reported thus far of pneumomediastinum associated with dermatomyositis and discuss the possible mechanisms involved. We conclude that pneumomediastinum is not an uncommon complication of dermatomyositis and that its aetiopathogenesis remains very unclear.