Inflammation

Question 1

What is inflammation?

Answer 1

Response to tissue damage by a wide range of stimuli

Stops when injurious agent is removed and inflammatory mediators are removed

Essential for wound healing

Question 2

Triggers of inflammation

Answer 2

Foreign body

Infection

Immune reaction s

Physical/chemical injury

Ischaemia/infarction

Question 3

Pros of inflammation

Answer 3

Limits tissue injury - can contain injurious agent

Removes dead tissues

Promotes specific immunity

Prepares for and initiates healing and repair

Question 4

Cons of inflammation

Answer 4

Allergies, hypersensitivity, autoimmunity - exaggerated inflammatory response

Can be persistent i.e. chronic inflammation

Question 5

How does it happen?

Answer 5

Many tissues and cells involved

• fluid and proteins of plasma
• circulating cells
• blood vessels
• constituents of connective tissue

Question 6

Vascular reaction of inflammation

Answer 6

To maximise movement of plasma proteins and circulating cells to site of injury

• changes in flow and vessel size
• increased vascular permeability

Results in hyperaemia, stasis and fluid exudation

Question 7

Cellular reaction of inflammation

Answer 7

Leucocyte extravasation (where liquid accidentally leaks into surrounding tissue)

• margination, rolling, adhesion to endothelium
• transmigration (reincarnation)
• migration through tissue

Question 8

Phagocytosis

Answer 8

Phagocytosis and enzyme release by neutrophils are the main benefits of accumlation of leucocytes at inflammatory sites

3 stepd:

• recognition of microorganisms
• engulfment
• killing and degradation

Question 9

5 hallmark signs of inflammation

Answer 9

Redness

Heat

Swelling

Pain

Loss of function

Question 10

Acute inflammation

Answer 10

Rapid response

Short lived

NEUTROPHILS predominate

Aim is complete resolution

Question 11

Outcomes of acute inflammation

Answer 11

Complete resolution

Healing by fibrosis (scar formation)

Abscess formation

Chronic inflammation

Question 12

Chronic inflammation

Answer 12

Prolonged

Can develop from acute inflammation but frequently doesn’t, unless:

• persistent infection
• prolonged exposure to toxins
• autoimmune reactions

Question 13

Outcomes of chronic inflammation

Answer 13

LYMPHOCYTES and MACROPHAGES predominate

Tissue destruction

Attempts at healing-proliferation of blood vessels, fibrosis and necrosis

Question 14

What can we do about it?

Answer 14

Medications

• NSAIDs
• anti-histamines
• steroids

Question 15

What happens if there isn’t an inflammatory response?

Answer 15

Defective inflammation

• increased chance of infection
• delayed wound healing
• tissue damage

E.g. immunodeficiency conditions, post-chemotherapy, medications

Question 16

Acute appendicitis

Answer 16

Peak age 10-30 years

Central abdominal pain localised to right iliac fossa

• worse on movement
• nausea/vomiting

Pyrexia, raised HR, raised WCC and CRP

Complications - abscess formation, perforation leading to peritonitis