PATHOLOGY - Inflammation

Question 1

What are the six key clinical signs of inflammation?

Answer 1

Redness
Heat
Swelling
Pain
Loss of function
Pyrexia

Question 2

What causes the redness seen with inflammation?

Answer 2

Redness associated with inflammation is due to vasodilation

Question 3

What causes the heat seen with inflammation?

Answer 3

Heat associated with inflammation is due to vasodilation

Question 4

What causes swelling associated with inflammation?

Answer 4

Swelling associated with inflammation is due to increased capillary permeability

Question 5

What causes the pain associated with inflammation?

Answer 5

Pain associated with inflammation is caused by the swelling exerting pressure on free nerve endings

Question 6

What causes the loss of function associated with inflammation?

Answer 6

Loss of function associated with inflammation is caused by the pain which reduces function, allowing time to heal

Question 7

What are the three main benefits of inflammation?

Answer 7

Dilutes/inactivates toxins and pathogens
Reduces function to allow time for healing
Increases temperature to induce vasodilation and inhibit the replication of pathogens

Question 8

What is the disadvantage of inflammation?

Answer 8

Prolonged or excessive inflammation can cause tissue damage

Question 9

What are the four inflammatory stimuli?

Answer 9

Infectious agents
Microbial toxins
Tissue damage
Foreign bodies

Question 10

Describe the vascular response to inflammatory stimuli

Answer 10

The vascular response consists of initial transient vasoconstriction followed by vasodilation to increase local blood flow. This is followed by increased vascular permeability to allow for leukocyte recruitment

Question 11

What causes the initial, transient vasoconstriction seen in the vascular response to inflammatory stimuli?

Answer 11

Endothelial cell contraction

Question 12

What mediates endothelial cell contraction?

Answer 12

Endothelial cell contraction is mediated by histamine

Question 13

What prolongs vascular permeability seen in the vascular response to inflammatory stimuli?

Answer 13

Endothelial cell retraction

Question 14

What mediates endothelial cell retraction?

Answer 14

Endothelial cell retraction is mediated by cytokines

Question 15

What is leukocyte mediated endothelial cell injury?

Answer 15

Leukocyte mediated endothelial cell injury is seen in the later stages of inflammation where the leukocytes can secrete toxic mediators which can cause damage to the endothelial cells

Question 16

What are five of the cell-derived inflammatory mediators?

Answer 16

Vasoactive enzymes
Arachidonic acid
Cytokines
Chemokines
Histamine

Question 17

What are three of the plasma protein inflammatory mediators?

Answer 17

Complement
Coagulation cascade
Kinin system

Question 18

What is the importance of mast cells in inflammation?

Answer 18

Mast cells are an important source of inflammatory mediators such as histamine, cytokines and chemokines

Question 19

What is transudate?

Answer 19

Transudate is leaked clear/yellowish fluid containing water, electrolytes and very few proteins

Question 20

What causes transudate to be leaked?

Answer 20

Transudate is leaked due to conditions which cause an increase in hydrostatic pressure and a decrease in oncotic pressure

Question 21

What is exudate?

Answer 21

Exudate is leaked fluid containing water, electrolytes, high numbers of proteins and cells (including erythrocytes, neutrophils (pus) and fibrin)

Question 22

What causes exudate to be leaked?

Answer 22

Exudate is leaked due to the vasodilation and increased vascular permeability caused by the vascular response to inflammation

Question 23

What are the five steps of leukocyte recruitment?

Answer 23

Margination
Rolling
Adhesion
Transmigration
Chemotaxis

Question 24

Which stages of leukocyte recruitment are mediated by cytokines and chemokines?

Answer 24

Adhesion, Transmigration and Chemotaxis are mediated by cytokines and chemokines

Question 25

Describe the margination step of leukocyte recruitment

Answer 25

During vasodilation, the blood flow slows allowing leukocytes to migrate from the central lumen to the periphery, close to the endothelial cell surface

Question 26

Describe the rolling step of leukocyte recruitment

Answer 26

Leukocytes tumble along the endothelial surface and undergo weak, transient adhesion to the endothelial surface

Question 27

Describe the adhesion step of leukocyte recruitment

Answer 27

Integrins present on the leukocyte surface firmly adhere to ligands on the surface of the endothelial cells

Question 28

Describe the transmigration step of leukocyte recruitment

Answer 28

Leukocytes undergo diapedesis

Question 29

Describe the chemotaxis step of leukocyte recruitment

Answer 29

Chemotaxis the the migration of leukocytes along a chemical gradient to the injury site

Question 30

What are the three stages of phagocytosis?

Answer 30

Recognition Engulfment Killing/degradation

Question 31

Describe the recognition step of phagocytosis

Answer 31

Phagocytic cells bind to specific cell surface receptors present on pathogens or to opsonins attached to pathogens

Question 32

Describe the engulfment step of phagocytosis

Answer 32

Pseudopods (cytoplasmic extensions) from the phagocytic cells engulf pathogens and form a phagosome around the pathogen

Question 33

Describe the killing/degradation step of phagocytosis

Answer 33

A lysosome containing reactive oxygen species binds to the phagosome to form a phagolysosome. The lysosome releases its contents, degrading the pathogen

Question 34

What are the other two terms used to describe neutrophilic inflammation?

Answer 34

Suppurative inflammation Purulent inflammation

Question 35

What are two common stimuli for neutrophilic inflammation?

Answer 35

Infection Non-infectious tissue damage

Question 36

What stimulates septic purulent inflammation?

Answer 36

Intracellular bacteria

Question 37

What defines eosinophilic inflammation?

Answer 37

Eosinophilic inflammation is when more than 10% of the inflammatory cell population is eosinophils

Question 38

What are five stimuli for eosinophilic inflammation?

Answer 38

Allergy/hypersensitivity Fungal infection Parasitic infection Eosinophilic granuloma Paraneoplastic disease

Question 39

What is the difference between granulomatous and pyogranulomatous inflammation?

Answer 39

Granulomatous inflammation is an aggregation of macrophages whereas pyogranulomatous inflammation is an aggregation of macrophages and neutrophils

Question 40

What is commonly associated with granulomas and pyogranulomas?

Answer 40

Chronic inflammation

Question 41

What are three common stimuli for lymphocytic inflammation?

Answer 41

Vaccinations Viral infection Chronic inflammation

Question 42

What are four of the causes of chronic inflammation?

Answer 42

Persistent infection Unresolved acute inflammation Autoimmunity Allergy/hypersensitivity

Question 43

What are four of the morphological signs of chronic inflammation?

Answer 43

Macrophages Tissue damage Fibrosis Angiogenesis