Abstract
We herein describe a 16-year-old boy with pneumomediastinum, pneumothorax, and subcutaneous emphysema as the initial symptoms of dermatomyositis (DM). His pneumomediastinum disappeared after strict bed rest and he was thereafter successfully treated with oral prednisolone and cyclosporine A. His condition was further complicated with mild interstitial lung disease, arrhythmia, and skin ulcers on his fingertips, right elbow, ear, and sacral region. Pneumomediastinum is a rare complication of DM and its pathogenesis remains unclear. We review the literature and discuss the possible mechanism of this disease.