acute inflammation

Question 1

what is inflammation?

Answer 1

the consequences of another effect: e.g. microbial infections, hypersensitivity reactions, physical or chemical agents

Question 2

what are some of the characteristics of inflammation?

Answer 2

red - due to dilation of the blood vessels;
hotness - due to blood vessel dilation; swollen - due to oedema and contribution from inflammatory cells; painful - stimulation of local nerve endings and chemical mediators; can also be a local or systematic loss of function

Question 3

what are the two phases of inflammation?

Answer 3

vascular phase: dilation and increased permeability of blood vessels;
exudative phase: fluid and cells escape from permeable venules

Question 4

what is one of the most important blood cells in inflammation?

Answer 4

neutrophils

Question 5

what is the difference between transudate and exudate?

Answer 5

transudate is normal interstitial fluid that leaks from capillaries due to hydrostatic pressure but returns via venules; exudate is the fluid that leaks from blood vessels during inflammation. with transudate, there is no net flow but with exudate there is; with exudate there is an increased permeability of blood vessels compared to in transudate; in transudate there is a low protein content but there is a high protein content in exudate

Question 6

what kind of proteins does exudate contain?

Answer 6

immunoglobins - destroy invading organisms

fibrinogen - synthesises fibrin

Question 7

what happens to the exudate once it has leaked from the blood vessels?

Answer 7

It is picked up by lymph vessels and taken to lymph nodes where it is used in the immune response.

Question 8

what are the chemical mediators in inflammation and what is their purpose?

Answer 8

chemical mediators include histamine and bradykinin. They stimulate gaps to form between the endothelial cells of 0.1-0.4 microns in post capillary venues. The endothelial cells are not damaged from this and return to normal.

Question 9

what happens to the exudate when it reaches the lymph nodes?

Answer 9

The leucocytes located there (mainly lymphocytes) produce specific antibodies

Question 10

what is lymphangitis?

Answer 10

inflammation of the lymph vessel

Question 11

what is lymphadenitis?

Answer 11

inflammation of local lymph nodes

Question 12

margination

Answer 12

when neutrophils roll on the blood vessel wall and attach. (before they squeeze out)

Question 13

the accumulation of what type of leucocytes in the ECM is a key feature of acute inflammation?

Answer 13

neutrophils

Question 14

how long do neutrophils last for?

Answer 14

24 hours

Question 15

what are neutrophils main role in the immune response?

Answer 15

to phagocytose and digest invading pathogens

Question 16

what is chemotaxis?

Answer 16

the movement of cells in the direction of increasing concentration of a chemical mediator

Question 17

how do neutrophils detect the chemical mediators?

Answer 17

via receptors on their surfaces

Question 18

what are opsonins?

Answer 18

chemicals which invading pathogens are coated in which help leucocytes to bind to them and greatly increase phagocytosis

Question 19

what is a characteristic of serous inflammatory response

Answer 19

protein rich fluid exudate (e.g. conjunctivitis)

Question 20

what is a characteristic of catarrhal inflammatory response

Answer 20

mucus hyper secretion (e.g. common cold)

Question 21

what is a characteristic of fibrinous inflammatory response

Answer 21

exudate is plentiful in fibrin (eg pericarditis)

Question 22

what is a characteristic of haemorrhagic inflammatory response

Answer 22

severe vascular injury (e.g. pancreatitis)

Question 23

what is a characteristic of suppurative inflammatory response

Answer 23

production of pus (e.g. abscesses)

Question 24

what is a characteristic of membranous inflammatory response

Answer 24

epithelium coated in fibrin

Question 25

what is a characteristic of pseudomembranous inflammatory response

Answer 25

superficial mucosal slough (eg C. difficile)

Question 26

what are some of the beneficial factors of acute inflammation?

Answer 26

dilution of toxins, entry of antibodies, increase delivery of materials to lymph nodes, usually results in resolution

Question 27

what are some of the harmful factors of acute inflammation?

Answer 27

digestion of normal tissue, swelling can cause problems (e.g. in the brain)