Evaluate for and treat for reversible causes of symptoms or exacerbation of symptoms
CXR:
Coal workers': diffuse nodular opacities, especially prominent in upper lung
Silicosis: Large conglomerate densities in upper lung
Asbestosis: linear streaking at bases, opacities, honeycomb changes if advanced
CT Chest
Best imaging for asbestosis, can detect parenchymal fibrosis and characterize pleural plaques
TB testing
Increased incidence of TB in patients with silicosis
Coal workers': diffuse nodular opacities, especially prominent in upper lung
Silicosis: Large conglomerate densities in upper lung
Asbestosis: linear streaking at bases, opacities, honeycomb changes if advanced
Best imaging for asbestosis, can detect parenchymal fibrosis and characterize pleural plaques
Increased incidence of TB in patients with silicosis
Pneumoconiosis
Interstitial pneumonias 
Atypical pneumonia
Lung malignancy
Bronchiectasis
Aspiration pneumonia or pneumonitis
Interstitial lung disease
Bacterial, viral, or fungal pneumonia