[Morphology of interstitial pneumonia (author's transl)]

The roentgenographic appearance of acute interstitialproliferative disease of the lung is described. This is based upon different single or combinated microscopic features: 1) Alveolitis -- 2) interstitial mesenchymal proliferation -- 3) tuberculous granulomas -- 4) lymphatic infiltrations. -- In the acute stage of the disease (in most cases with unknown etiology) steroid therapy shown rapid success. Early lung biopsy should be performed to establish the diagnosis and to avoid pulmonary fibrosis.