Fig. 2. Histological (hematoxylin and eosin stain) and ultrastructural findings of the lung. (A) Uniformly diffuse interstitial fibrosis and inflammatory cell infiltration are observed (× 40, scale bar = 1 mm). (B) Eosinophilic proteinaceous material and alveolar macrophages are identified in alveolar spaces (× 200, scale bar = 200 μm). (C, D) Ultrastructurally, the alveoli are lined by type II pneumocytes, which have a relatively normal appearing lamellar form of surfactant in shape and number.