What are is histologic findings in acute silicosis?

BAL: excludes infection, EP, alveolar hemorrhage. see thick opaque effluent similar to proteinosis. Cytology see foamy macrophages bright positive image in PAS. in acute one nodules are rarely seen and poorly developed, alveoli filled largely of phopholipids or surfactant Thickened interstitium with inflammatory cells, minimal fibrosis,