acute inflammation

Question 1

define inflammation

Answer 1

the local physiological response to tissue injury (a reaction to injury involving cells such as neutrophils and macrophages - from lec)

Question 2

give examples of cells involved in inflammation

Answer 2

neutrophils, macrophages, lymphocytes, endothelial cells, fibroblasts

Question 3

give features of neutrophils

Answer 3

short-lived
first inflammatory cells in acute inflammation
cytoplasmic granules with enzymes that kill bacteria
dise at the scene of inflammation
release chemokine (that attract other inflammatory cells e.g. macrophages)

Question 4

give features of acute inflammation

Answer 4

sudden onset
short duration 
usually resolves
neutrophils 
dilation of vessels
exudate- vascular leakage of protein rich fluid

Question 5

give features of chronic inflammation

Answer 5

slow onset/sequel to acute
long duration
may never resolve/slow resolution
lymphocytes, plasma cells and macrophages

Question 6

neutrophils do not carry out phagocytosis? T or F

Answer 6

False

Question 7

what do endothelial cells do in inflammation?

Answer 7

become sticky to allow inflammatory cells to adhere to them
become porous to allow inflammatory cells to pass into tissues
grow into areas of damage to form new capillaries

Question 8

what happens to capillaries in inflammation and why

Answer 8

they fill with blood as there is vasodilation of arterioles and opening of pre-capillary sphincters

Question 9

why is there oedema?

Answer 9

as the endothelial lining becomes more porous, plasma protein leaves the vessels and fluid leaves the vessels by osmosis, as the oncotic pressure is greater outside the vessels

Question 10

What are the steps of migration of neutrophils?

Answer 10

1. margination of neutrophils
2. pavemetation of neutrophils
3. pass between endothelial cells
4. pass through basal lamina and migrate into adventitia

Question 11

What systems are interlinked in inflammation?

Answer 11

Four plasma enzymatic cascade systems:

coagulation, fibrinolytic, kinin and complement

Question 12

give an example of acute inflammation and info about it

Answer 12

acute appendicitis 
unknown cause
neutrophils
dilation of blood vessels
inflammation of serial surfaces
pain
result:
1. appendix surgically removed  2. inflammation resolves
3. appendix bursts giving generalised peritonitis and possible death

Question 13

give examples of the stages of acute peritonitis

Answer 13

1. oedema and swelling with dilated blood vessels
2. pus
3. rupture of contents

Question 14

what is the difference between exudate and transudate?

Answer 14

exudate has a high protein content because they result from increased vascular permeability
transudates have a low protein content as the vessels have normal permeability characteristics

Question 15

give an example of a drug use for inflammation

Answer 15

ibuprofen (NSAIDs)

Question 16

what are the beneficial effects of inflammation?

Answer 16

destruction of invading microorganisms

walling off of an abscess cavity, preventing spread of infection

Question 17

What are the harmful effects of inflammation?

Answer 17

1. may produce disease
   e. g. an abscess in the brain may act as a space-occupying lesion, compressing vital surrounding structures
2. fibrosis from chronic inflammation may distort the tissues and permanently alter their function
3. digestion of normal tissues
4. swelling
5. inappropriate inflammatory response

Question 18

define acute inflammation

Answer 18

initial and often transient series of tissue reactions to injury

Question 19

chronic inflammation

Answer 19

subsequent and prolonged tissue reactions following the initial response (beware though not always following acute inflammation)

Question 20

causes of acute inflammation

Answer 20

microbial infections -pyogenic bacteria and viruses
hypersensitivity reactions - parasites, tubercle bacilli
physical agents - trauma, ionising radiation, heat, cold
chemicals - corrosives, acids, alkalis, reducing agents
tissue necrosis - ischaemic infarction (due to peptides released from dead tissue)
bacterial toxins that lead directly to inflammation

Question 21

define hypersensitivity reaction

Answer 21

occurs when an altered state of immune responsiveness causes an inappropriate or excessive immune reaction that damages tissues

Question 22

what are the essential macroscopic appearances of acute inflammation?

Answer 22

Rubor
Calor
Tumor
Dolor
loss of function

Question 23

explain rubor

Answer 23

dilation of small blood vessels within the damaged area

Question 24

explain calor

Answer 24

hyperaemia in periphery due to vasodilation

systemic fever due to chemical mediators of inflammation

Question 25

explain tumor

Answer 25

this is selling of the area due to oedema - the accumulation of fluid in the extravascular space due to fluid exudate also from the physical mss of inflammatory cells migrating to the area formation of connective tissue contributes to swelling in later stages

Question 26

explain dolor

Answer 26

pain 1. from stretching and situation of tissues due to oedema and pus under pressure in an abscess cavity 2. chemical mediators e.g. bradykinin, prostaglandins and serotonin cause pain

Question 27

explain loss of function

Answer 27

1. movement inhibited by pain | 2. severe swelling may physically immobilise the tissues

Question 28

what three processes are important in acute inflammation?

Answer 28

1. change in vessel calibre and flow 2. increased vascular permeability and formation of the fluid exudate 3. formation of the cellular exudate - neutrophils

Question 29

what are the three causes of increased vascular permeability?

Answer 29

1. immediate transient chemical mediators e.g. histamine, bradykinin, NO, C5a, leukotriene, PAF 2. immediate sustained severe direct vascular injury e.g. trauma 3. delayed prolonged endothelial cell injury - x-rays, bacterial toxins

Question 30

What causes neutrophil adhesion to the endothelial surface?

Answer 30

histamine and thrombin, interleukins, C5a, leukotriene and PAF cause up-regulation of adhesion molecules on the surface of endothelial cells

Question 31

What do endogenous chemical mediators cause?

Answer 31

``` vasodilation emigration of neutrophils chemotaxis increased vascular permeability itching and pain ```

Question 32

Name some endogenous chemical mediators that cause vasodilation

Answer 32

``` histamine VIP NO PAF prostaglandins ```

Question 33

Name some endogenous chemical mediators that cause increased vascular permeability

Answer 33

``` histamine bradykinin NO C5a leukotriene B4 PAF ```

Question 34

name some endogenous chemical mediators that cause neutrophil chemotaxis

Answer 34

leukotriene B4 | Il-8

Question 35

name special macroscopic appearances of acute inflammation

Answer 35

``` serous suppurative membranous pseudomembranous necrotising (gangrenous) So Special Macroscopic Parts Now ```

Question 36

what are the outcomes of acute inflammation?

Answer 36

resolution suppuration organisation progression to chronic inflammation

Question 37

what are the systemic effects of acute inflammation?

Answer 37

``` pyrexia constitutional symptoms weight loss reactive hyperplasia of the RES haematological changes amyloidosis ```

Question 38

what is resolution?

Answer 38

complete restoration of tissue to normal

Question 39

what is suppuration?

Answer 39

formation of pus - living and dead neutrophils, bacteria, cell debris, e.g. abscess

Question 40

What is organisation?

Answer 40

replacement of tissue by granulation tissue as part of repair (granulation tissue consists of small blood vessels in a connective tissue matrix with myofibroblasts)

Question 41

why does acute inflammation sometimes progress to chronic?

Answer 41

causative agent not removed