Inflammation Flashcards

1
Q

List the 3 phases of acute inflammation

A
  1. Vascular phase
  2. Exudative cellular phase
  3. Outcome
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is included in the vascular phase of acute inflammation

A
  • Change in vessel calibre
  • Increased vascular permeability
  • Formation of fluid exudates
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What occurs in the exudative cellular phase of acute inflammtion

A
  • Adhesion of neutrophils
  • Neutrophil migration
  • Diapedesis
  • Neutrophil chemotaxis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

List the causes of acute inflammation

A
  • Microbial infection
  • Hypersensitivity reactions
  • Chemical agents
  • Physical agents e.g. trauma
  • Tissue necrosis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

List the macroscopic signs and symptoms of acute inflammation

A
  • Redness (rubor)
  • Heat (calor)
  • Swelling (tumour)
  • Pain (dolor)
  • Loss of function
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Outline the triple response to injury in vessels

A
  1. Flush - dull red line due to capillary dilatation
  2. Flare - red irregular zone due to arteriolar dilatation
  3. Weal - zone of oedema due to fluid exudate in the intravascular space
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Why does fluid leave the vessels in acute inflammation

A
  • Capillary hydrostatic pressure is increased
  • More fluid leaves vessels than returns
  • An exudate is formed
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

List the stages of cellular exudate formation in acute inflammation

A
  1. Margination of neutrophils
  2. Neutrophil adhesion to leucocytes and endothelial surfaces
  3. Neutrophil migration
  4. Diapedesis (escape of red cells from capillaries)
  5. Neutrophil chemotaxis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What increases leucocyte surface adhesion molecule expression

A
  • Complement C5a
  • Leucotriene B4
  • TNF
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What increases endothelial expression of adhesion molecules

A
  • IL-1
  • Endotoxins
  • TNF
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What stimulates neutrophil chemotaxis

A
  • Leukotriene B4

- IL-8

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the action of histamine in inflammation

A
  • Vasodilation

- Transiently increases vascular permeability

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the action of prostaglandins in inflammation

A
  • Potentiate increased vascular permeability
  • Platelet aggregation
  • Platelet disaggregation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the role of C5a and C3a

A
  • Chemotactic for neutrophils
  • Increase vascular permeability
  • Trigger release of histamine from mast cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Describe the kinin system

A
  • Activated by coag factor 7
  • Converts prekallikrein to kallikrein
  • Kallikrein cleaves kininogen to release bradykinin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the role of bradykinin

A

Controls vascular permeability and is a chemical mediator of pain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

How are macrophages stimulated

A

Local infection (endotoxins) or injury

18
Q

What do macrophages produce and why

A
  • IL-1
  • TNF

Both stimulate endothelial cells to produce adhesion molecules which bind and activate neutrophils

19
Q

What is the characteristic cell of acute inflammatory exudates

A

Neutrophil polymorphs

20
Q

What cells dominate in acute inflammation

A

Neutrophils

21
Q

What cells dominate in chronic inflammation

A
  • Lymphocyte
  • Macrophages
  • Plasma cells
22
Q

Describe suppurative inflammation

A
  • Production of pus (dying and degenerate neutrophils)
  • May become walled off by fibrin to become and abscess
  • May form empyema
23
Q

Give an example of membranous inflammation

A

Grey membrane seen in pharyngitis due to diphtheria

24
Q

Give an example of pseudomembranous inflammation

A

C.diff colitis (superficial mucosal inflammation and ulceration with sloughing of mucosa, fibrin, mucus, inflammatory cells)

25
Q

Benefits of exudate production

A
  • Dilution of toxins
  • Arrival of antibodies
  • Transport of drugs
  • Fibrin formation
  • Delivery of oxygen/nutrients
  • Stimulation of the immune response
26
Q

How is resolution of acute inflammation achieved

A
  1. Phagocytosis of bacteria
  2. Fibrinolysis
  3. Phagocytosis of debris by macrophages
  4. Resolution of vascular dilatation
27
Q

Describe the process of organisation with respect to inflammation

A

Replacement of tissue by granulation tissue

28
Q

What circumstances favour granulation

A
  • Excess fibrin formation
  • Substantial necrotic tissue
  • Exudate and debris cannot be removed or discharged
29
Q

How does acute inflammation progress to chronic inflammation

A
  • If the causative agent is not removed

- Tissues become organised with the cellular exudate changing to lymphocytes, plasma cells, macrophages, and giant cells

30
Q

What are the causes of chronic inflammation

A
  • Primary chronic inflammation
  • Progress from acute inflammation
  • Recurrent episodes of acute inflammation
  • Transplant rejection
31
Q

List the causes of primary chronic inflammation

A
  • Resistance of infective agents to phagocytosis and killing e.g. TB
  • Foreign body reactions
  • Autoimmune diseases e.g. RA
  • Specific diseases of unknown aetiology e.g. UC
  • Primary granulomatous disease e.g. CD
32
Q

What type of acute inflammation is most likely to progress to chronic inflammation

A

Suppurative - inadequate drainage of pus which is deep seated

33
Q

Outline the pathology of non-specific chronic inflammation

A
  1. Tissue macrophages recruited by bloodstream monocytes
  2. T-helper cells activate B lymphocytes to produce plasma cells via IL-4
  3. Plasma cells produce antibodies against the persistent antigen
  4. Plasma cells divide under the influence of IL-1 from macrophages
  5. A degree of scarring occurs
  6. Fibrosis is stimulated by TGF-beta
34
Q

What are some of the possible macroscopic appearances of chronic inflammation

A
  • Chronic ulceration
  • Chronic abscess
  • Caseating granulomatous inflammation
  • Thickening of hollow viscus
  • Fibrosis
35
Q

What type of collagen is laid down in scarring

A

Type 1

36
Q

What is a granuloma

A

Aggregate of epitheloid histiocytes

37
Q

List the features of epitheloid histiocytes

A
  • Arranged in clusters
  • Little phagocytic activity
  • Produce ACE
  • Caseous necrosis may occur
  • Can be converted to Giant cells
38
Q

Where is TNF primarily secreted from

A

Macrophages

39
Q

What type of giant cell is characteristically seen in TB

A

Langhans cells - horseshoe arrangement of peripheral nuclei at one pole of the cell

40
Q

What infections cause granulomatous disease

A
  • Mycobacteria e.g. TB
  • Atypical fungi
  • Parasites
41
Q

What drugs cause granulomatous inflammation

A
  • Allopurinol
  • Phenylbutazone
  • Sulphonamides