Inflammation

Question 1

What is inflammation?

Answer 1

The local physiological response to noxious stimuli, such as: infection and/or tissue injury. Manifestation of disease, not a disease.

Question 2

What is acute inflammation?

Answer 2

The initial response to noxious stimuli.

Question 3

List 4 features of acute inflammation.

Answer 3

1) sudden onset
2) short duration
3) usually resolves
4) neutrophils are the main cell involved

Question 4

List 6 causes of acute inflammation.

Answer 4

1) microbial infection
2) bacterial toxins
3) tissue necrosis
4) hypersensitivity reaction
5) physical agents, e.g. trauma or temperature
6) chemical agents, e.g. corrosives or reducing agents

Question 5

List 3 processes of acute inflammation.

Answer 5

1) increased vascular diameter
2) increased vascular permeability
3) formation of cellular exudate

Question 6

List 4 outcomes of acute inflammation.

Answer 6

1) resolution
(usual result)
2) suppuration
(pus formation)
3) repair and reorganisation (necrosed tissue --> granulation tissue)
(excess necrosis)
4) chronic inflammation
(persistence of stimuli)

Question 7

What happens during reorganisation? (4)

Answer 7

1) macrophages phagocytose dead tissue and acute inflammatory exudate
2) granulation tissue (vascular connective tissue) fills the damage site
3) fibroblasts in granulation tissue produce collagen
4) fibrous scar tissue forms

Question 8

What is chronic inflammation?

Answer 8

Long term inflammation.

Question 9

List 4 causes of chronic inflammation.

Answer 9

1) primary chronic inflammation
2) progression of acute inflammation
3) recurrent acute inflammation
4) transplant rejection

Question 10

List 4 features of chronic inflammation.

Answer 10

1) slow onset / progression of acute inflammation
2) long duration
3) may never resolve
4) macrophages, lymphocytes and plasma cells are the main cells involved

Question 11

List 3 functions of neutrophils.

Answer 11

Involved in acute inflammation.

1) phagocytic
2) secrete granules
3) secrete cytokines

Question 12

List 2 functions of macrophages.

Answer 12

Involved in chronic inflammation.

1) phagocytic
2) antigen presentation

Question 13

List 3 things macrophages phagocytose.

Answer 13

1) inflammatory exudate
2) damaged cells
3) necrosed cells

Question 14

List 2 functions of B lymphocytes.

Answer 14

1) antigen presentation

2) secrete antibodies - plasma cells

Question 15

What is the function of helper T lymphocytes?

Answer 15

Release cytokines to recruit and activate other immune cells.

Question 16

List 3 functions of endothelial cells.

Answer 16

1) become sticky to allow inflammatory cells to adhere
2) become porous to allow inflammatory cells to pass into tissues
3) grow into areas of damage to form new capillary vessels

Question 17

What is the function of fibroblasts.

Answer 17

Repair - synthesise collagen in inflamed areas - scarring.

Question 18

What are epithelioid histiocytes?

Answer 18

Tissue-resident macrophages with specific features, e.g. Kuppfer cells

Question 19

List 2 features of epitheliod histiocytes.

Answer 19

1) little phagocytic activity

2) adapted for secretion

Question 20

What is a granuloma?

Answer 20

Collection of epithelioid histiocytes. May also contain lymphocytes and histiocytic giant cells.

Question 21

How do histiocytic giant cells form?

Answer 21

Multiple epithelioid histiocytes trying to phagocytose the same large indigestible particulate, hence fusing into a multinucleate giant cell.

Question 22

Define exudate.

Answer 22

Extravascular mass of cells and fluid due to increased vascular permeability.

Question 23

What do exudate contain?

Answer 23

High protein content.

Question 24

What do exudate result in?

Answer 24

Formation of oedema, hence swelling.

Question 25

List the 5 features of inflammation.

Answer 25

1) calor - heat
2) dolor - pain
3) rubor - redness
4) tumor - swelling
5) loss of function

Question 26

What is the cause of rubor?

Answer 26

Dilation of small blood vessels in inflamed area.

Question 27

What is the cause of calor?

Answer 27

Vascular dilation, resulting in increased blood flow causes delivery of warm blood. Only seen in peripheries.

Question 28

What is the cause of tumor?

Answer 28

Accumulation of extravascular fluid due to exudate forms an oedema.

Question 29

List 2 causes of dolor?

Answer 29

1) inflammatory oedema causing stretching and distortion of tissue
2) chemical mediators of inflammation induce pain, e.g. prostaglandins, serotinin and bradykinin

Question 30

List 2 causes of loss of function?

Answer 30

1) conscious and reflex inhibition of movement of inflamed area
2) severe swelling physically immobilises tissue

Question 31

List the 2 main constituents of granulation tissue and their functions.

Answer 31

1) myofibroblasts (myocytes and fibroblasts) —> contract edges of wound and secrete collagen and extracellular matrix
2) capillary loops —> provide nutrients and leukocytes and take away cellular waste

Question 32

When does resolution at inflammation site occur? (2)

Answer 32

1) initiating factor has been removed

2) tissue undamaged/able to regenerate

Question 33

When does repair at inflammation site occur? (2)

Answer 33

1) initiating factor still present

2) tissue damaged/unable to regenerate

Question 34

Define wound healing?

Answer 34

Skin repairs itself after damage.

Question 35

List the 4 phases of wound healing.

Answer 35

1) haemostasis
2) inflammation
3) proliferation
4) maturation

Question 36

Name the 2 types of wound healing.

Answer 36

1) healing by primary intention

2) healing by secondary intention

Question 37

When does healing by primary intention occur?

Answer 37

When the wound is thin/tissue surfaces have been closed, e.g. stitches.

Question 38

When does healing by secondary intention occur?

Answer 38

When the wound is large with considerable tissue loss.

Question 39

Describe healing by primary intention. (5)

Answer 39

1) exudate contains fibrinogen
2) weak fibrin join forms
3) fibroblast synthesise collagen
4) strong collagen join forms
5) epidermis regrows

Question 40

Describe healing by secondary intention. (5)

Answer 40

1) exudate contains fibrinogen
2) weak fibrin join forms
3) myofibroblast synthesise collagen
4) strong collagen join forms
5) myofibroblasts contract, decreasing space between dermal edges
6) epidermis regrows

Question 41

List the 4 differences between healing by primary and secondary intention.

Answer 41

1) repair time
2) scarring
3) chances of infection
4) fibroblasts vs myofibroblasts

Question 42

What occurs during repair?

Answer 42

Replacement of damaged tissue unable to regenerate with fibrous tissue.

Question 43

List 2 cells that cannot regenerate?

Answer 43

1) myocardial cells

2) neurones (except peripheral nerves - slow rate of 1mm per day)

Question 44

List 6 cells that can regenerate?

Answer 44

1) hepatocytes
2) pneumocytes
3) haemocytes
4) osteocytes
5) gut epithelium
6) skin epithelium

Question 45

Increased plasma concentration of which enzyme is a marker for granulomatous disease?

Answer 45

Angiotensin converting enzyme.