Uncategorized
  • Anatomical and Pathophysiological Basis:
    • Refers to the scarring and thickening of the interstitial tissue of the lungs.
    • The interstitium is the network of connective tissue that supports the alveoli, including blood vessels, lymphatics, and extracellular matrix.
    • Characterized by deposition of excessive collagen and extracellular matrix within the interstitial spaces.
  • Radiological Characteristics:
    • On Chest X-ray (CXR):
      • Reticular (net-like) opacities, particularly in the lung bases and peripheries.
      • Loss of lung volume with a “shrunken” appearance.
      • May show honeycombing in advanced cases.
    • On High-Resolution CT (HRCT):
      • Reticular patterns: fine or coarse linear opacities due to thickened interstitial tissue.
      • Honeycombing: clustered cystic spaces, typically subpleural and basal.
      • Traction bronchiectasis: dilated airways due to lung distortion.
      • Ground-glass opacities may be present in early stages but are less prominent in fibrosis-dominant disease.
  • Common Diseases and Conditions Associated:
    1. Idiopathic Causes:
      • Idiopathic Pulmonary Fibrosis (IPF).
    2. Autoimmune and Connective Tissue Diseases:
      • Systemic sclerosis (scleroderma).
      • Rheumatoid arthritis-associated interstitial lung disease.
      • Sjögren?s syndrome.
    3. Environmental and Occupational Exposures:
      • Asbestosis.
      • Silicosis.
      • Chronic hypersensitivity pneumonitis.
    4. Drug-Induced Lung Injury:
      • Amiodarone, bleomycin, methotrexate.
    5. Infectious Causes:
      • Post-infectious fibrosis (e.g., following severe pneumonia or tuberculosis).
    6. Genetic Conditions:
      • Hermansky-Pudlak syndrome.
      • Familial pulmonary fibrosis.
  • Clinical Relevance:
    • Leads to restrictive lung disease with reduced lung compliance and impaired gas exchange.
    • Symptoms include progressive dyspnea, dry cough, and reduced exercise tolerance.
    • Diagnosis often requires a combination of clinical, radiological, and sometimes histopathological findings.

 

Difference Between
Pulmonary Fibrosis and Interstitial Fibrosis:

  • Pulmonary fibrosis is a general term encompassing all lung scarring, whereas interstitial fibrosis specifically refers to scarring of the interstitial lung tissue.
  • All interstitial fibrosis is pulmonary fibrosis, but not all pulmonary fibrosis is interstitial.