Medicine distinguishes two groups of pulmonary fibrosis.
Secondary pulmonary fibrosis
In this case, a triggering underlying disease can be detected. The following are possible:
- Infections with fungi or bacteria
- Autoimmune diseases (e.g. sarcoidosis)
- Connective tissue disorders (e.g. scleroderma or Sjörgen syndrome)
- Rheumatic diseases
- Vascular inflammation
- Lung disease caused by inhaled dust
- Pollutants such as tobacco smoke or gases
- Some medicines (e.g. in the context of chemotherapy)
- Radiation (e.g. after radiation therapy)
- Water accumulation in the lungs (e.g. the development of certain heart and kidney diseases)
- Certain forms of lung cancer
Idiopathic pulmonary fibrosis
In this case, no trigger can be found for the pulmonary fibrosis, which happens in up to 50 percent of the cases. Doctors also call this "idiopathic interstitial pneumonia" (IIP). This means "lung inflammation of the cell interstices of unknown cause".