Inflammation and healing

Question 1

What is acute inflammation?

Answer 1

Initial and often transient series of tissue reactions to injury

Question 2

What is chronic inflammation?

Answer 2

subsequent and prolonged tissue reactions following the initial response to injury

Question 3

What is hypersensitivity?

Answer 3

Inappropriate and excessive immune reaction that damages tissue (altered immune response)

Question 4

What is a granuloma?

Answer 4

Aggregate of epithelioid histiocytes

Question 5

What is granulation tissue?

Answer 5

component of healing and repair by 2nd intention

Question 6

What is a sinus tract?

Answer 6

An abnormal connection between an abscess and mucosal surface

Question 7

What is a fistula?

Answer 7

An abnormal connection between skin and mucosal surface (or 2 mucosal surfaces)

Question 8

What is cholecystitis?

Answer 8

Inflammation of the gall bladder

Question 9

What are the macroscopic appearances of acute inflammation?

Answer 9

Rubor, dolor, calor, tumor (and loss of function)

Question 10

What are the 4 outcomes of acute inflammation?

Answer 10

Resolution, organisation (granulation –> scar), suppuration, progression to chronic inflammation

Question 11

What is organisation?

Answer 11

Capillary + fibroblast in growth –> altering the tissue (it is an outcome of acute inflammation)

Question 12

How is acute inflammation beneficial?

Answer 12

bordering of an abscess in the brain, prevents the spread of infection

Question 13

Give 5 causes of acute inflammation

Answer 13

tissue necrosis, chemical agents, bacterial toxins, microbial infections, physical agents (Trauma, UV…), Hypersensitivity reactions

Question 14

What type of fluid is found in acute inflammation?

Answer 14

exudate (protein rich)

Question 15

What causes increased vascular permeability?

Answer 15

direct vessel trauma, chemical mediators (C3a + C5a, NO, bradykinin, histamine…)

Question 16

Describe the normal flow of neutrophils

Answer 16

Axial flow

Question 17

How is the cellular exudate formed?

Answer 17

Chemoattraction causes neutrophils to marginate (flow along vessel wall), adhesion and emigration –> chemotaxis occurs after this

Question 18

What do neutrophils contain to kill pathogens in a phagosome?

Answer 18

ROS: H2O2, OH, O2…

Question 19

What are the two initial chemical mediators involved in acute inflammation?

Answer 19

Histamine and thrombin

Question 20

what 4 enzyme cascades are involved in acute inflammation?

Answer 20

coagulation system, kinin system, fibrinolytic system, complement system

Question 21

Does chronic inflammation usually result from acute inflammation?

Answer 21

No - it is a primary event

Question 22

What can chronic inflammation lead to?

Answer 22

Amyloidosis

Question 23

Give 3 causes of chronic inflammations

Answer 23

Resistance of infective material to phagocytosis + intracellular killing (TB, leprosy), primary granulomatous disease (Crohn’s, sarcoidosis…), UC, autoimmune diseases (RA, pernicious anaemia, hashimoto’s thyroiditis), asbestosis/coal/silica, progression from acute inflammation, transplant rejection (Chronic rejection)

Question 24

What cells are found in chronic inflammation

Answer 24

Macrophages, lymphocytes, plasma cells, multinucleate giant cells….

Question 25

Give 4 examples of macrophages

Answer 25

kupffer cells, alveolar macrophages, osteoclasts, microglial cell

Question 26

What type of giant cell is seen in TB?

Answer 26

Langhan's giant cell

Question 27

Give 3 types of giant cells

Answer 27

Langhan's, Foreign body and Touton giant cells

Question 28

Is there caseation in sarcoidosis?

Answer 28

No - non-caseating granulomatous inflammation

Question 29

give 5 diseases with granulomatous inflammation

Answer 29

TB, leprosy, sarcoidosis, Crohn's, wegener's granulomatosis, giant cell arteritis

Question 30

What is the difference between resolution and repair?

Answer 30

In resolution the initiating factor is removed and tissue is undamaged (able to regenerate)

Question 31

give an example of resolution?

Answer 31

Liver regeneration, lobar pneumonia

Question 32

Why does pneumonia resolve?

Answer 32

Pneumocytes can regenerate

Question 33

What are the 3 types of healing in skin?

Answer 33

Abrasian, 1st intention and 2nd intention

Question 34

give examples of cells that can regenerate

Answer 34

hepatocytes, pneumocytes, blood cells, gut epithelium, skin epithelium, osteocytes

Question 35

give examples of cells that don't regenerate

Answer 35

Neurones, myocardial cells

Question 36

What is repair?

Answer 36

Replacement of damaged tissue by fibrous tissue (collagen produced by fibroblasts)

Question 37

What is a "scab" composed of?

Answer 37

Layers of fibrin

Question 38

What is left intact in an abrasian?

Answer 38

Hair follicle and sweat gland

Question 39

Describe the processes of 1st intention healing

Answer 39

Incised wound --> weak fibrin joint/bridge + coagulated blood --> capillares proliferate, fibroblasts produce collagen, epidermal growth

Question 40

Explain the process of 2nd intention healing

Answer 40

Tissue has been removed --> formation of granulation tissue --> organisation --> epithelial regeneration

Question 41

What composes granulation tissue?

Answer 41

Myofibroblasts + capillary loops (collagen deposited)

Question 42

What do myofibroblasts do?

Answer 42

contract to pull the wound together

Question 43

How do capillary loops form?

Answer 43

Angiogenesis (VEGF)

Question 44

What are the complications of scarring?

Answer 44

Deformity, reduced range of movement/function, bowel stenosis and obstruction...