Lung Diseases, Interstitial

**Definition:** A diverse group of lung diseases that affect the lung parenchyma. They are characterized by an initial inflammation of PULMONARY ALVEOLI that extends to the interstitium and beyond leading to diffuse PULMONARY FIBROSIS. Interstitial lung diseases are classified by their etiology (known or unknown causes), and radiological-pathological features.

**Tree numbers:** - C08.381.483

**Synonyms:** - Diffuse Parenchymal Lung Diseases - Interstitial Lung Diseases - Interstitial Lung Disease - Diffuse Parenchymal Lung Disease