A process in which normal lung tissues are progressively replaced by FIBROBLASTS and COLLAGEN causing an irreversible loss of the ability to transfer oxygen into the bloodstream via PULMONARY ALVEOLI. Patients show progressive DYSPNEA finally resulting in death.

Synonyms: Alveolitis, Fibrosing, Alveolitides, Fibrosing, Pulmonary Fibroses, Fibrosing Alveolitis, Pulmonary Fibrosis, Idiopathic Diffuse Interstitial Pulmonary Fibrosis, Fibrosing Alveolitides, Fibroses, Pulmonary, Fibrosis, Pulmonary