[A case of rheumatoid lung disease in which lung involvement preceded arthritis].

A 75-year-old man was admitted because of dyspnea on exertion and diffuse pulmonary interstitial shadows. An open lung biopsy revealed unclassified interstitial pneumonia. The abnormal shadow subsided spontaneously. Three years later, however, rheumatoid arthritis developed with a simultaneous relapse of interstitial pneumonitis, which was alleviated by steroid therapy. We report here the rheumatoid lung disease that preceded the onset of arthritis, together with a review of the literature.