Pneumonitis

Inflammatory process involving the lung parenchyma, usually noninfectious, characterized by alveolar and interstitial inflammation that may be acute or chronic and can progress to pulmonary fibrosis if persistent or severe.

Causes

• Hypersensitivity and inhalational causes

  • Aspergillus exposure

  • Chemical fumes

  • Pesticides

  • Animal fur or bird proteins

  • Wood dust

  • Mold exposure

• Radiotherapy-induced lung injury

• Medications associated with drug-induced lung injury

  • Antibiotics

  • Chemotherapy agents

  • Cardiac medications (amiodarone)

• Aspiration pneumonitis

• Autoimmune and connective tissue disease causes

  • Rheumatoid arthritis

  • Systemic sclerosis (scleroderma)

  • Systemic lupus erythematosus (SLE)

  • Dermatomyositis and polymyositis

  • Vasculitis involving the lungs

• Other causes

  • Idiopathic interstitial pneumonitis

  • Eosinophilic pneumonitis

  • Acute respiratory distress syndrome (ARDS)-related lung inflammation