Acute Inflammation

Question 1

Inflammation definition

Answer 1

A biological reaction to noxious stimuli

Inflammation is a protective process that delivers leukocytes and plasma proteins to the site of injury to protect the body from further damage

Question 2

Cardinal signs of inflammation

Answer 2

redness, swelling, heat, pain, loss of function

Question 3

Causes of inflammation

Answer 3

• Infection
• Trauma
• Burns/frostbite
• Allergic reactions
• Tissue necrosis

Question 4

Acute inflammation

Answer 4

In acute inflammation the inflammatory response occurs immediately and lasts hours/days

Question 5

Inflammatory responses

Answer 5

1. Vascular dilation increases blood flow
2. Structure changes to the vessels allow leukocytes to enter the tissues
3. Leukocytes accumulate at the injury site

Question 6

Vascular dilation mechanism

Answer 6

Results in heat & redness

Induced by histamine, bradykinin & nitric oxide

One of the earliest signs of acute inflammation

Question 7

Structure changes mechanism

Answer 7

Results in swelling/ oedema

The endothelial cells contact and detach due to cell injury, increasing intracellular spaces

There is also increased transport of fluid and proteins through endothelial cells

Question 8

Leukocyte emigration mechanism

Answer 8

Leukocytes move into the tissues by extravasation/diapedesis

Leukocytes are attracted to the site by chemotaxis

The leukocytes adhere to the endothelium via adhesion molecules that are only expressed during inflammation

Question 9

Leukocyte chemotactic receptors

Answer 9

Leukocytes recognise chemoattractants via receptors

• Toll-like receptors = recognise microbial products
• GCPRs = recognise bacterial peptides
• Opsonin receptors = recognise antibodies
• Cytokine receptors = recognise IFN

Question 10

Fibrinous inflammation

Answer 10

Characterised by fibrinous exudate which can lead to scar formation and limit function

Question 11

Purulent inflammation

Answer 11

Characterised by pus filled fluid of neutrophils and dead cells

Typical of staphylococcal infections

Question 12

Serous inflammation

Answer 12

Characterised by copious effusion of non-viscous serous fluid

E.g = skin blister

Question 13

Ulcerative inflammation

Answer 13

Characterised by necrotic loss of tissue from the surface, exposing lower layers and leading to the formation of an ulcer

Question 14

Outcomes of acute inflammation

Answer 14

• Complete recovery
• Healing by connective tissue replacement
• Progression to chronic inflammation