Inflammation

Question 1

What does inflammation allow?

Answer 1

protective response geared towards removing the cause and consequence of the injury
allows potential healing

Question 2

list the cell types and soluble factors involved?

Answer 2

cells = neutrophils, macrophage, lymphocytes, eosinophils, mast cells
soluble factors = cytokines, antibodies, complement system, coagulation system

Question 3

define acute inflammation

Answer 3

rapid non-specific response to cellular injury orchestrated by mediators released by injured cells

Question 4

what response does acute inflammation involve?

Answer 4

leukocyte and vascular

Question 5

define chronic inflammation

Answer 5

persistent inflammatory response that may arise from acute inflammation

Question 6

name a type of chronic inflammation

Answer 6

granulomatous inflammation

Question 7

what are signs of acute inflammation? what causes them

Answer 7

rubor - slow blood flow gives redness
calor - histamine vasodilation
tumor - histamine increased permeability and oedema
dolor - swelling and pain

Question 8

what are the 3 main components of acute inflammation?

Answer 8

alteration in the calibre of blood vessels to increase flow
structural changes to the microvasculature to allow protein and leukocytes to leave circulation
emigration, accumulation and activation of leukocytes at the focus of injury

Question 9

what does vasodilation cause? what is it induced by? what is it followed by?

Answer 9

heat and redness
induced by nitric oxide and histamine
increased permeability of microvasculature (leads to turbulent flow)

Question 10

summarise the mechanism for increased vascular permeability and causes

Answer 10

endothelial cells contract
increase interendothelial spacing
causes = histamine, NO, endothelial injury, leukocyte mediated vascular injuryy

Question 11

how is histamine released? what does it cause?

Answer 11

mast cell degranulation after IgE bind to cell

vasodilation and vascular permeability

Question 12

define exudate

Answer 12

fluid with high protein, cellular debris content and specific gravity which has escaped from blood vessels and has been deposited in tissues due to inflammation

Question 13

define transudate

Answer 13

low protein, cell content and specific gravity caused by disturbances in hydrostatic and colloid osmotic pressure

Question 14

what is the function of exudate?

Answer 14

the fluid dilutes pathogen and allows soluble mediators to spread
the protein e.g. fibrin wall off pathogens to stop it spreading

Question 15

name and describe the exudate types

Answer 15

serous = fluid filled, lower protein content
fibrinous = high fibrin content due to traumatic injury
purulent = pus filled, combo of fibrin, inflammatory cells, debris and fluid

Question 16

What are the key leukocytes in the initial phase of acute inflammation? why?

Answer 16

neutrophil and monocyte/macrophage
kill bacteria and eliminate foreign and necrotic material, produce multiple factors and mediators that interact with other cells (degranulate)

Question 17

summarise the mechanism by which neutrophils migrate into the tissue site

Answer 17

margination, rolling, adhesion to activated endothelium via loose selectin bonds then strong integrin bonds, transmigration across endothelium and migration via chemotaxis

Question 18

what receptors are activated in a leukocyte response?

Answer 18

toll-like receptors - for microbial products
g-protein coupled receptors - bacterial peptides
opsonic receptors - for IgG and C3b
cytokine receptors - for IFN-gamma

Question 19

How is acute inflammatory response terminated?

Answer 19

mediators and neutrophils have short half life
macrophages, mast cells and lymphocytes release anti-inflammatory products
injury cause is removed

Question 20

list histological features of acute inflammation

Answer 20

many neutrophils, mast cells and eosinophils

Question 21

how does acute inflammation evolve to chronic inflammation?

Answer 21

myofibre breakdown, fewer neutrophils, other cells involved

Question 22

list causes of chronic inflammation

Answer 22

persistent infection, prolonged exposure to toxins, autoimmunity, foreign body

Question 23

what is chronic inflammation characterised by?

Answer 23

mononuclear cell infiltrate (macrophage, lymphocyte, plasma cells)
tissue destruction induces by persistent inflammatory agent of the inflammatory cells
attempts at healing by replacement of damaged tissue with connective tissue FIBROSIS

Question 24

what is the role of macrophages and what does the role depend on?

Answer 24

phagocytosis, amplification of inflammation, wound repair and fibrosis, anti-inflammatory
depends on the activation pathways

Question 25

how does the action of macrophages differ in acute and chronic?

Answer 25

acute - destroy agent and stimulate others to do the same | chronic - persist and destroy tissue

Question 26

list the cells involved in chronic inflammation

Answer 26

T cells, plasma cells, eisonphils, mast cells, neutrophils (if coexisting with acute)

Question 27

what is prominent in chronic inflammation?

Answer 27

angiogenesis

Question 28

what is chronic inflammation lacking?

Answer 28

exudate, less necrosis

Question 29

list the histological feature of chronic inflammation

Answer 29

abundant macrophages, lymphocytes and plasma cells | many fibroblasts producing granulomatous tissue

Question 30

list histological features of granulomatous inflammation

Answer 30

macrophages in middle and lymphocytes on outside | fused macrophages seen at later stage

Question 31

list causes of granulomatous inflammation

Answer 31

infection, foreign material, reaction to tumours, immune disease

Question 32

list the differences between acute and chronic

Answer 32

``` acute/chronic neutrophils/monocytes histamine/cytokine necrosis/scar tissue few days/weeks, year, months ```

Question 33

what is a good outcome of inflammation?

Answer 33

removal of agent, cessation of inflammation, healing of tissue

Question 34

what is a local bad outcome of inflammation?

Answer 34

excess local tissue and scarring, secondary effects on nearby tissue

Question 35

what is a systemic bad outcome of inflammation?

Answer 35

systemic inflammatory reaction, secondary multi organ failure

Question 36

define resolution wound healing

Answer 36

regeneration of normal functional parenchymal cells

Question 37

define repair wound healing

Answer 37

connective and scar tissue formation

Question 38

how does resolute occur?

Answer 38

tissue cells are capable of regeneration and little structural damage done as cells need framework e.g. basement membrane to build on

Question 39

when and how does repair occur?

Answer 39

tissue loss is too great and cells can't regenerate tissue replaced with fibrous scar tissue fibroblast produce collagen collagen is a string scar ye remodelling - reorganisation of collagen fibres for maximal tensile strength angiogenesis

Question 40

what hinders repair?

Answer 40

poor nutrition, vitD deficiency, mineral deficiency, suppressed inflammation, poor blood supply, persistent foreign body, movement

Question 41

what is keloid formation?

Answer 41

XS collagen deposition

Question 42

what are contractures?

Answer 42

fibrous scar tissue contacts as it matures and can limit joint mobility

Question 43

how can organ function be impaired?

Answer 43

fibrous scars in organs limits function