Pulmonary fibrosis is a chronic lung condition characterized by the
progressive scarring and thickening of the lung interstitium, leading
to stiff, less elastic lungs that impair normal breathing. This scarring
can result from a variety of causes, including autoimmune diseases
(like rheumatoid arthritis or scleroderma), environmental exposures
(such as asbestos, silica, or other inhaled toxins), chronic
infections, and certain medications. In many cases, the cause is
unknown, leading to the term idiopathic pulmonary fibrosis (IPF).
The pathogenesis involves ongoing injury to the alveoli, followed by
abnormal healing and excessive deposition of fibrous tissue, which
replaces normal lung architecture. Symptoms typically include
persistent dry cough, progressive shortness of breath, fatigue, and
reduced exercise tolerance. Diagnosis is based on a combination of
clinical evaluation, pulmonary function tests (PFTs) showing a
restrictive pattern, and imaging, particularly high-resolution CT
scans, which reveal reticular patterns, honeycombing, and traction
bronchiectasis.