Drug-related
- Amiodarone
- Antibacterials (nitrofurantoin, sulfonamides)
- Antineoplastics (bleomycin, cyclophosphamide, methotrexate, nitrosoureas)
- Antirheumatics (gold salts, penicillamine)
- Phenytoin
Environmental & occupational
- Inorganic dust (asbestos, silica, hard metals, beryllium)
- Organic dust or hypersensitivity pneumonitis (thermophilic actinomycetes, avian antigens, Aspergillus spp.)
- Gases, fumes, vapors (chlorine, isocyanates, paraquat, sulfur dioxide)
- Ionizing radiation
- Talc (injection drug users)
Infections
- Disseminated fungus (coccidioidomycosis, blastomycosis, histoplasmosis)
- Disseminated mycobacteria
- Pneumocystis jiroveci pneumonia
- Viruses
Primary pulmonary syndromes
- Idiopathic fibrosing interstitial pneumonia [idiopathic pulmonary fibrosis (IPF)]:
- Acute interstitial pneumonia (AIP)
- Desquamative interstitial pneumonia (DIP)
- Nonspecific interstitial pneumonitis (NSIP)
- Usual interstitial pneumonia (UIP)
- Respiratory bronchiolitis-associated interstitial lung disease (RB-ILD)
- Bronchiolitis obliterans-organizing pneumonia (BOOP)
Systemic disorders
- Acute respiratory distress syndrome (ARDS)
- Amyloidosis
- Ankylosing spondylitis
- Autoimmune disease: dermatomyositis, polymyositis, rheumatoid arthritis, systemic sclerosis (scleroderma), systemic lupus erythematosus
- Chronic eosinophilic pneumonia
- Goodpasture's syndrome
- Idiopathic pulmonary hemosiderosis
- Inflammatory bowel disease
- Eosinophilic granuloma (Langerhans cell histiocytosis, histiocytosis X)
- Lymphangitic carcinomatosis
- Lymphangioleiomyomatosis (LAM)
- Pulmonary edema
- Pulmonary venous hypertension
- Sarcoidosis
- Wegener's granulomatosis