Interstitial Pulmonary fibrosis
Def.
group of diseases characterized by infiltration of the interstitial tissue of the lung by abnormal tissue.
Site of pathology
= Interstitial tissue (in between alveoli)
= Peri-alveolar tissue.
Pathogenesis
Exposure to dust (for example)
► Trigger immune system
Or ► Inflammatory reaction
Or ► Direct toxicity

interstitial infiltration with inflammatory cells.

diffusion defect
(
O2)

recovery if the cause interstitial pulmonary
is avoided fibrosis (irreversible)
(I.P.F)
Causes
1- Dust (occupational lung diseases)

Inorganic dust Organic dust
= pneumoconiosis = allergic pneumonitis
2- Sarcoidosis
SLE
3- Collagen diseases
Rheumatoid diseases.
Ankylosing spondylitis.
4- Idiopathic
Hamman Rich $
C/P
Features of interstitial pulmonary diseases:
1- Cause e.g. history of exposure, arthropathy.
Cough
Cyanosis O2
2- 5C Crepitation (fine leathery character)
Clubbing
Core pulmonale
Investigations
1- X-ray, diffuse lung infiltration (military shadow)
2- Blood gases diffusion defect -
O2
3- CT scan.
4- Lung biopsy (open or transbronchial)
Treatment:
1. Avoid cause
2. Steroids before fibrosis
3. Antioxidant.
Bronchodilators.
Cytotoxic drugs in some cases.

Source: Internal Medicine Book of Dr.Osama Mahmoud (Ain Shams University)