[Clinicopathological features of interstitial pneumonia associated with amyopathic dermatomyositis]

We studied clinicopathological characteristics of interstitial pneumonia associated with amyopathic dermatomyositis. The subjects comprised two men and three women, and their mean age was 58.2 years. All subjects had cruptions specific for dermatomyositis, but had no signs of myositis. They all presented with acutely or subacutely developed coughing and dyspnea. Results of tests for anti-Jo-1 antibody were negative in all cases. Chest X-ray films showed infiltrations or streaky shadows, or both in the middle and lower lung fields. Analysis of bronchoalveolar lavage fluid revealed abnormally high percentages of lymphocytes and neutrophils. In one patients a specimen obtained by open lung biopsy showed homogeneous cell infiltrations in alveolar septa and regional alveolar damage. That patient was successfully treated with cyclosporin and corticosteroids in early phase of the disease. The other four patients received immunosuppressive agents after respiratory failure developed. All four died despite having received high-dose corticosteroid and immunosuppressive therapy. Examination of autopsy specimens showed diffuse alveolar damage.