Inflammation

Question 1

What is exudate?

Answer 1

Exudate (also called pus) is fluid and the dissolved materials within that leaks from blood vessels into/onto nearby tissues. Exudate may ooze from cuts or areas of inflammation.

Question 2

What is the nature of serous exudate?

Answer 2

Watery fluid found in blisters etc.

Question 3

What is suppurative exudate?

Answer 3

Cloudy fluid that contains white blood cells and bacteria

Question 4

What is haemorrhagic exudate?

Answer 4

Bloody fluid that indicates vascular damage.

Question 5

During inflammation what is the purpose of endothelial cell retraction?

Answer 5

Increases the width of slip pores allowing proteins to leak out

Question 6

During inflammation, what is achieved by the proteins leaking out after endothelial cell retraction?

Answer 6

Clotting proteins form clots in the interstitial fluid keeping the antigens and antibodies in the same place

Question 7

Why does swelling initially feel soft then harden?

Answer 7

Initially the interstitial space is filled with exudate, clots then form and the swelling becomes harder

Question 8

How do complement proteins affect inflammation?

Answer 8

Compliment proteins amplify the antigen/antibody complexes (this is the complement cascade). Inflammation increases i.e. volume of histamine and prostaglandins increases

Question 9

What is responsible for the pain of inflammation?

Answer 9

Prostaglandins and bradykinin

Question 10

What is the process of white blood cell delivery to damaged tissue?

Answer 10

Increased capillary flow increases filtration causing blood to become more concentrated. The plasma that usually runs against the endothelium leaks out, allowing white blood cells that are usually in the centre of vessels to touch the sides. Neutrophils reach slip pores and ooze out

Question 11

What white blood cells predominantly are in new sites of inflammation?

Answer 11

Neutrophils

Question 12

What white blood cells predominantly are in old sites of inflammation?

Answer 12

Macrophages

Question 13

What are the main systemic affects of inflammation?

Answer 13

Lymph adenopathy
Leucocytosis
Fever

Question 14

What is the process of lymph adenopathy?

Answer 14

Increased lymph node size. An increase in capillary permeability causes more fluid to drain into the interstitial spaces increasing tissue hydrostatic pressure which is then drained into the lymphatic system which increases in pressure. Lymph nodes can accumulate scar tissue and be left permanently hard and large

Question 15

What is leukocytosis?

Answer 15

Increased production of lymphocytes which leads to an elevated white blood count in the blood

Question 16

What is the main pathophysiological cause of fever?

Answer 16

Neutrophils

Question 17

How do neutrophils cause fever?

Answer 17

Neutrophils release pyrogens that reset the hypothalamus thermostat.

Question 18

What stimulates inflammation?

Answer 18

Tissue damage
Antigens

Question 19

What are the two different types of tissue damage signals?

Answer 19

Pathogen Associated Molecular Patterns (PAMPs)
Damage Associated Molecular Patterns (DAMPs)

Question 20

What happens once mast cells are activated?

Answer 20

They release histamines, cytokines & lipid mediators (leukotrienes & prostaglandins). These chemicals travel around and cause endothelial cell retraction, the endothelial cells release nitric oxide which increases the vasodilation.

Question 21

What are the four causes of cellular injury?

Answer 21

Hypoxia
Toxins
Infectious agents
Physical injury

Question 22

What is extravasation?

Answer 22

Extravasation is the leakage of a fluid out of its contained space into the surrounding area, especially blood or blood cells from vessels. In the case of inflammation, it refers to the movement of white blood cells through the capillary wall, into the surrounding tissues.

Question 23

How do complement proteins attract leukocytes?

Answer 23

Chemotaxis and by tagging the pathogenic surface with C3b which the leukocytes recognise

Question 24

What are the 5 cardinal signs of inflammation?

Answer 24

Swelling
Erythema (redness)
Heat
Pain
Loss of function

Question 25

Where does inflammation happen?

Answer 25

Vascularised tissue

Question 26

Does inflammation happen at poorly vascularised areas?

Answer 26

Yes it can, but not always and it may take longer

Question 27

What are the main functions of prostaglandins in inflammation?

Answer 27

Vasodilation
Endothelial cell retraction
Noceceptor stimulation (pain)
Fever
Inhibit platelet aggregation

Question 28

What types of prostaglandins are important in inflammation?

Answer 28

COX-2 prostaglandins

Question 29

Where are mast cells located?

Answer 29

Mast cells are found throughout the body in loose connective tissue. Some are randomly dispersed in the tissue. They tend to concentrate near blood vessels, where the cell is more elongated. In the skin, concentrates can also be found near follicles, sebaceous glands, and sweat glands

Question 30

Where are dendrite cells found?

Answer 30

Tissues that have contact with the outside environment, such as lung mucosa, epithelial cells of the skin, and the linings of the nose and the gastrointestinal tract

Question 31

Why are dendrite cells pivotal to inflammation?

Answer 31

They are the only antigen-presenting cell capable of stimulating naive T cells.

(They act as messengers between the innate and adaptive immune systems)

Question 32

Where are mast cells not located?

Answer 32

Mature mast cells are present only in tissue and are not found in circulation.

Question 33

What causes swelling during inflammation?

Answer 33

Extravasation

Question 34

What causes heat and erythema during inflammation?

Answer 34

Capillary dilation

Question 35

What can cause pain during inflammation?

Answer 35

Trauma of initial injury and prostaglandins trigger noceceptors (pain receptors)

Question 36

What can cause loss of function during inflammation?

Answer 36

Pain
Swelling and pressure on nerves and vessels - can be severe, treat as an emergency

Question 37

How do steroids reduce/control inflammation?

Answer 37

Steroids reduce the production of chemicals that cause inflammation. This helps keep tissue damage as low as possible. Steroids also reduce the activity of the immune system by affecting the way white blood cells work.

Their most important action is switching off multiple activated inflammatory genes (inhibition of HAT and recruitment of HDAC2).