Chronic Inflammation

Question 1

What is the purpose of inflammation?

Answer 1

1) remove cause of injury
2) Remove necrosis
3) Initiate repair

Question 2

What immune cells cause chronic and acute inflammation?

Answer 2

Acute = neutrophils
Chronic = Machrophages, Lymphocytes, fibroblasts.

Question 3

Chronic inflammation can be primary or develop from acute. In what ways can this happen?

Answer 3

Progression from acute to chronic inflammation is most common is supporative (pus forming) inflammation.

Pus can form an abscess.

Granulation and fibrous tissue forms.

Recurrent acute inflammation can lead to chronic

Question 4

What are the features of chronic inflammation?

Answer 4

1) Infiltration with mononuclear cells
2) Tissue destruction
3) Healing by fibrosis (new fibrous scar tissue from granulation tissue)
4) (exudation fluid NOT prominent)

Question 5

What is the role of macrophages in chronic inflammation?

Answer 5

1) macrophages are V. importnant in Chronic Inflammation
2) they secrete cytokines at sight of damage which recruit monocytes
3) Macrophages proliferate in the damaged tissue and get immobilised.

Question 6

What are monocytes?

Answer 6

Monocytes are in the blood stream and differentiate into macrophages or dendritic cells once in tissue

Question 7

What is the persistent accumulation of macrophages in chronic inflammatory tissue due to?

Answer 7

1) continued recruitment of monocytes (due to secretion of cytokines)
2) local proliferation of macrophages
3) immobilisation in macrophages

Question 8

What happens during wound healing ?

Answer 8

1) Granulation tissue froms by :
2) Angiogenesis (development of new blood vessels)
3) Fibroblasts deposit collagen
4) Inflammatory cells

Question 9

What is fibrosis?

Answer 9

thickening or scarring of connective tissue during repair of damaged tissue

Question 10

Give examples of granulomatous diseases?

Answer 10

Bacterial:
TB
Leprosy

Parasitic:
Schistosomiasis

Fungal:
Cryptococcus

Unknown:
Sarcoidosis
Crohn’s

Question 11

What is a granuloma?

Answer 11

Granuloma = nodule of activated macrophages (epithelioid histiocytes), lymphocytes and histiocytic giant cells (ie. giant macrophages)

Question 12

What are histiocytic giant cells and how to the develop?

Answer 12

• when material is indigestible to macrophages Histiocytic giant cells can form.
• When 2 or more macrophages try to engulf the same particle a giant cell can form
• they are not phagocytic

Question 13

How is inflammation associated with cardiovascular diseases ?

Answer 13

• Chronic inflammation in response to MI
• Atheroma formation:
• Macrophages process lipids in plaque and become foam cells.

Question 14

What are the causes of chronic inflammation?

Answer 14

• acute Infl
• persistent infection
• autoimmunity
• prolonged exposure to toxins