[A case of dermatomyositis complicated with pneumomediastinum that was successfully treated with cyclosporin A].

We reported the case of a 39-year-old man with dermatomyositis (DM) complicated with subcutaneous emphysema and pneumomediastinum during steroid therapy. The patient had complained of muscle weakness, dyspnea and skin eruption on his anterior chest wall 6 months prior to admission. He was diagnosed as having DM on the basis of an elevation in myogenic enzymes, myogenic changes in electromyography, a skin biopsy and a muscle biopsy. Chest roentgenogram revealed interstitial pneumonia (IP) in the lower lobes of the lungs. The administration of prednisolone (60 mg/day) was initiated, which resulted in improvement of DM. Fifteen days after the initiation of the steroid therapy, the patient developed subcutaneous emphysema and pneumomediastinum. Additional administration of cyclosporin A (CsA) enabled us to rapidly taper the dose of prednisolone without aggravating the diseases. Several reports have shown that vasculitis might be involved in the pathogenesis of pneumomediastinum in DM patients. Infection and tissue fragility due to steroid therapy worsen the outcome of those patients. CsA therapy may improve the outcome through the anti-vasculitic- and steroid sparing-effects.