[Recurrent pneumomediastinum in the course of interstitial pneumonia associated with dermatomyositis].

A 59-year-old woman with dermatomyositis suffered pneumomediastinum twice during steroid therapy for aggravated myositis. In both instances, pneumomediastinum occurred when the patient's aggravated myositis was in remission. Plain chest X-ray films showed a slit-like air lucency around the left pulmonary artery. This indicated that air entered the mediastinum through the left hilum. Although pneumomediastinum associated with dermatomyositis is considered to be fatal, in our patient each instance of pneumomediastinum spontaneously disappeared very quickly. The favorable course of our patient seemed to be associated with her high elevated levels of serum creatine kinase and seropositive results for anti-Jo-1 antibody.