2.4 Acute inflammation

Question 1

Cardinal signs of inflammation:

Answer 1

1. reddening - increased blood flow to the area
2. swelling - exudation of fluid from dilated blood vessels into the inflamed tissue
3. increased heat - increased blood flow: the temp of the inflamed portion approximates to internal body temp
4. pain - due to chemical mediators released into damged tissue, and by local pressure on nerve endings from the exudate
5. loss of function - reluctance to use the inflamed portion

Question 2

___ and ___ are the underlying mechanism in acute inflammation

Answer 2

vascular permeability and migration of white blood cells

Question 3

____ is important in inflammation?

Answer 3

white blood cells, particularly macrophages

Question 4

Inflammation can result from?

Answer 4

an immune response
ex: injury to tissues could arise from the mechanisms designed to protect them from irritant agents

Question 5

Causes​ of inflammation:

Answer 5

• microorganisms and parasites
• Trauma: mechanical, chemical, and thermal insult
• Aberrant immune response: hypersensitivity and autoimmune​ disease
• malignant neoplasms

Question 6

Classification of inflammation:

Answer 6

• acute
• chronic
  **but with some overlap

Question 7

acute:

Answer 7

sudden onset and may last for a few hours to a few days; vascular, humoral, and cellular alterations cause the 5 cardinal signs of inflammation as a result of exposure of tissues to injurious sunstances

Question 8

sequelae:

Answer 8

1. death
2. resolve by regeneration in association with host defense mechanisms ( may be assisted by therapeutic measures)
3. undergo repair by fibrosis
4. become chronic - (goes through a subacute phase first), depending upon the persistence​ of the agent and the amount of damage

Question 9

stages​ of acute inflammation Stage 1: vascular phase

Answer 9

1. initial phase: transient (secs)
   - arteriole constriction (white line)
   - smooth muscle response
2. Hyperaemia = (mins - days)
   - arteriole and capillary dilation
   - chemical mediators

Question 10

Normal Capillary bed =

Answer 10

• closed precapillary sphincter
• empty capillaries​

Question 11

Capillary bed in acute inflammation: chemical mediators

Answer 11

• damaged tissue and plasma cause the ​open precapillary sphincter
• most capillaries are full
• dilation

Question 12

acute inflammation: chemical mediators leads to what?

Answer 12

Phase 2: exudative phase
- mast cells

Question 13

Exudative phase: increased vascular permeability is due to?

Answer 13

endothelial cell contraction

Question 14

Stage 2: exudative phase

Answer 14

• endothelial cell contraction is caused by histamine released by mast cells
• also direct endothelial injury:
• physical damage
• toxic agents
  -infection
• enzymes
• oxygen free radicals

Question 15

exudative phase result:

Answer 15

escape (exudation) of protein-rich fluid from blood into surrounding tissue

Question 16

contents of fluid exudate:

Answer 16

• water and electrolytes
• Plasma proteins (albumin, globulin, fibrinogen)
• Red blood cells
• Platelets

Question 17

Statge 3: migration of leucocyte

Answer 17

1. margination/ pavementing
   - altered blood flow and loss of axial stream
   - expression of adhesion molecule
2. Chemotaxis
   - neutrophils move along chemotactic gradient
   - chemotaxins attract and activate leukocytes, bacterial products, fibrin degradaiation products, complement derived factors
   cytokines, tissue breakdown products
3. emigration via intercellular junctions
   - motile cells force an opening
   - basement membrane is breached`

Question 18

where are neutrophils formed?

Answer 18

bone marrow

Question 19

neutrophil production time?

Answer 19

7 days - half life in blood 6 hrs

Question 20

How often are neutrophils replaced​?

Answer 20

twice a day

Question 21

onece neutrophils enter the tissues they do not return to where?

Answer 21

the blood

Question 22

Where are most neutrophils lost?

Answer 22

the mucous membrane of the body ex: gut, urinary, and respiratory tract

Question 23

neutrophils contain?

Answer 23

multilobed nuclei and are indistictly granulated

Question 24

Neutrophil function:

Answer 24

killing of microorganisms, tumor cells, and elimination of foreign material

Question 25

Neutrophil function: (2)

Answer 25

1. phagocytosis of microorganisms or foreign material and fusion of phagosome with lysosomes​ to kill or degrade material

Question 25

Neutrophil function: (2)

Answer 25

1. phagocytosis of microorganisms or foreign material and fusion of phagosome with lysosomes​ to kill or degrade material 2. secretion / release of granules into exudate to enhance acute inflammatory response

Question 26

Neutrophil recruitment:

Answer 26

- loosely stick to walls, and roll along - at the ​junction between endothelial cell, migrate out - travel to the ​site of damage - serous discharge becomes cloudy - degranulate

Question 27

where are eosinophils​ found?

Answer 27

in bone marrow, have similar life span to neutrophils

Question 28

When there are a large number of eosinophils in a tissue, as with parasitic conditions, they impact a ___ colour to the tissue

Answer 28

greenish

Question 29

eosinophils contain?

Answer 29

multilobed nuclei and distinct granules in the cytoplasm

Question 30

eosinophils are prominent in?

Answer 30

parasitic infections and local allergic reactions (IgE)

Question 31

Where are mast cells found?

Answer 31

heavily granulated​ mononuclear cells found in tissues

Question 32

Mass cell tissue lifespan?

Answer 32

4-12 weeks depending on location

Question 33

mast cells degranulate in ?

Answer 33

tissue injury, releasing histamine, heparin, and serotonin - chemical mediators of vasodilation​, chemotaxis, and pain

Question 34

When are mast cells critical?

Answer 34

in the ​initiation of acute inflammatory response

Question 35

where are basophils formed?

Answer 35

in bone marrow

Question 36

Basophils contain ?

Answer 36

multilobed nucleated cells with bluish granules in cytoplsm

Question 37

basophils have granules similar to those of both

Answer 37

neutrophils and mast cells

Question 38

basophils are important in ?

Answer 38

IgE mediated injury to tissues (allergic reactions