Chronic Inflammation

Question 1

What is the definition of chronic inflammation

Answer 1

This is an inflammatory response of prolonged duration that is provoked by the persistence of the inflammatory stimulus to the tissue

Question 2

Give an example of the chronic inflammatory process and explain how this is chronic inflammation

Answer 2

Active chronic peptic ulcers of the stomach = result of a balance between continuing tissue damage and eradication of the damaging stimulus versus healing and scar formation

Question 3

What etiological agents produce chronic inflammation

Answer 3

• Infectious organisms that avoid or resist host defences e.g. TB
• Infectious organisms that have the ability to persist due to location, pleural abscess or joint infections
• ## Autoimmune diseases

Question 4

What are some of the key effector cells for the immune/inflammatory response

Answer 4

• Lymphocytes
• Plasma cells
• Macrophages (Histiocytes, monocytes)
• Fibroblasts - Often referred to as “Chronic inflammatory cells”

Question 5

What are macrophages derived from

Answer 5

Blood monocytes

Question 6

What are macrophages sitimulated by

Answer 6

Stimulated by chemokines and chemotactic agents released by T- lymphocytes

Question 7

What are the functions of macrophages

Answer 7

• Digestion/killing of cells
• Digestion of ECM
• Stimulation of fibroblasts and CT
• Angiogenesis
• Recruitment of other inflammatory cells

Question 8

What is the cellular infiltrate of acute and chronic inflammation

Answer 8

Acute = Mainly neutrophils
Chronic = Monocytes/macrophages and lymphocytes

Question 9

What histological appearances can you see in chronic inflammation

Answer 9

• Mixed inflammatory cell infiltrate = lymphocytes, plasma cells and macrophages
• Healing by fibrosis, granulation tissue, angiogenesis, scar tissue
• Cell death, necrosis, apoptosis, abscess formation

Question 10

What is a granuloma

Answer 10

This is a small area of inflammation that is a collection of epithelioid macrophages surrounded by lymphocytes and occasionally plasma cells

Question 11

Describe granulomatous inflammation responses

Answer 11

• Distinctive chronic inflammatory reaction with a predominant cell type, which is the activated macrophage that has an epithelioid appearance

Question 12

Give examples of granulomatous inflammation

Answer 12

• TB
• Sarcoidosis
• Crohn’s disease
• Foreign Body

Question 13

Which bacteria causes tuberculosis

Answer 13

Mycobacterium Tuberculosis

Question 14

What does tuberculosis cause to cells

Answer 14

Caseous Necrosis

Also causes langerhan’s cells to form by the fusion of epithelioid cells (macrophages).

Question 15

Name some bacterial granulomatous diseases

Answer 15

Leprosy
Syphilis
Cat-scratch disease

Question 16

Name a parasitic granulomatous disease

Answer 16

Schistosomiasis

Question 17

Name a fungal granulomatous disease

Answer 17

Cryptococcus

Question 18

Name a granulomatous disease that can be caused by inorganic dusts

Answer 18

Silicosis

Question 19

What is tolerance

Answer 19

The ability for the body to distinguish self from non-self

Question 20

Give examples of inflammatory autoimmune disorders

Answer 20

Rheumatoid arthiritis

Hashimoto’s thyroiditis

Question 21

What is rheumatoid arthritis and what does it cause

Answer 21

• This is a chronic inflammatory condition that is associated with rheumatoid factor
• Leads to joint destruction and deformity as a result of chronic inflammatory process taking place within joint synovium

Question 22

What stain is used to identify the presence of tuberculosis

Answer 22

The Ziehl Nielsen stain

Question 23

What is Hashimoto’s thyroiditis and what does it cause

Answer 23

• This is an autoimmune disease of the thyroid that produces goitre and hypothyroidism
• Caused by antibodies attaching to TSH receptors in the thyroid gland
• Causes massive chronic inflammatory cell response within thyroid with glandular destruction and endocrine disturbance

Question 24

Describe what type 1 sensitivity is (chronic inflammation)

Answer 24

Anaphylactic - Mast cell mediated release of IgE antibody in response to an allergen, leads to release of histamine and inflammatory mediators and subsequent inflammation

Question 25

Describe what type 2 hypersensitivity is

Answer 25

Results from circulating antibodies attacking and binding to specific body tissues leading to inflammatory response. Damage by complement activation or cytotoxicity, may stimulate/block a receptor

Question 26

What is an example of Type 2 hypersensitivity disorder and describe it

Answer 26

Goodpastures syndrome - reaction between an antibody and the basement membrane and endothelium of capillaries in the glomerulus in the kidney and lungs. Results in chronic inflammation and subsequent damage to kidneys and lungs

Question 27

Describe what type 3 hypersensitivity is

Answer 27

Due to the deposition of antigen-antibody complexes within vessel walls and tissues resulting in inflammation and tissue damage

Question 28

Give an example of type 3 hypersensitivity

Answer 28

SLE glomerulopathy due to deposition of immune complexes within the glomerulus, leading to inflammation and damage

Question 29

Describe what type 4 hypersensitivity is

Answer 29

• Cell mediated reaction
• Caused by sensitized T-lymphocytes
• Stimulate macrophages and other chronic inflammatory cells

Question 30

Give and example of type 4 hypersensitivity

Answer 30

• TB

- Rejection of organ grafts

Question 31

What is the outcome of chronic inflammation

Answer 31

• Healing by scarring
• Perforation
• Chronicity
• Depends on local factors, host immune response, persistent disease