pathology

1. Chronic Inflammation
MR:MAHMOUD IBRAHIM

2. Chronic Inflammation
• Definition: reaction which is slow on onset and prolonged
in duration.
• Characteristic histological features:
1.Greater tissue destruction than acute inflammation
(necrosis and hemorrhage).
2.Mononuclear infiltrates (lymphocytes, plasma cells, and
macrophages).

3. 3. Granulation tissue formation and scarring (fibrosis) with
little or absent exudate.

4. Causes of chronic inflammation
• 1- Persistent infections
– Organisms usually of low toxicity that invoke delayed hypersensitivity
reaction - M. tuberculosis
• 2- Prolonged exposure to potentially toxic agents
– Exogenous agents include silica which causes silicosis

5. Macroscopic appearance of CI
• Chronic ulcers; peptic ulcer.
• Abscess; chronic osteomyelitis.
• Thickening of the wall hollow viscous; cholecystitis, crohn’s
disease.
• Granulomatous inflammation; TB.
• fibrosis

6. Gastric ulcer

8. Chronic lung abscess

9. Chronic inflammation due to Influenza

11. Granuloma
• Distinctive pattern of chronic inflammation characterized by
presence of an activated macrophage with a modified epithelial
like appearance, named epithelioid cells.
• Fusion of epithelioid cells together results in formation of
multinucleated giant cells:

12. 1. Langerhans type: horse-shoe appearance of nuclei. It is
characteristic for TB.
2. Foreign body type: random arrangement of nuclei. It is found with
Asbestosis and Silicosis.

13. Pulmonary TB (Caseous necrosis and scarring)

14. Pulmonary TB: multiple granulomas.

15. Renal TB

16. Foreign body giant cell Langerhans giant cell