Introduction to inflammation

Question 1

Define acute inflammation

Answer 1

the immediate defensive reaction of tissue to injury, in which vascular and exudative processes predominate

Question 2

Define chronic inflammation

Answer 2

Prolonged and persistent inflammation; which may be a continuation of acute inflammation, or the result of an insidious insult, characterised by scar tissue formation

Question 3

Explain the purpose and benefits of inflammation

Answer 3

purpose is to rid the body of the initial cause of injury, to break down cells damaged by injury in order to regenerate and repaid.
Innate immunity
beneficial effects =
1. the delivery of immune cells and proteins
2. Dilution of toxins
3. eliminate substance and allow repair/regeneration OR stimulate secondary immune system
4. Leaky vessels = increase fluid into area therefore drugs can enter.

Question 4

What are the microscopic features of acute inflammation

Answer 4

Vascular changes:
- Vasodilation
- Increased blood flow

Exudative changes:
- Increased permeability due to increased interendothelial spaces
- Movement of fluid, proteins and cells from the vasculature into tissues that are damaged

Neutrophils (leukocytes):
emigrate out of blood system into tissue
accumulate in area of trauma
try to eliminate immune response trigger via phagocytosis

Question 5

What are the macroscopic features of acute inflammation

Answer 5

erythema - redness of skin
oedema - swelling
warmth
pain
loss of function

Question 6

List the outcomes of acute inflammation

Answer 6

1. Resolution
2. Persisting injury –> Chronic inflammation

Question 7

List the outcomes of chronic inflammation

Answer 7

Repair and return
ongoing inflammation
change in tissue function
scarring and dysfunction
catastrophe (organ/patient death)

Question 8

What are the key microscopic features of chronic inflammation

Answer 8

1. Lymphocytes and macrophages
2. Tissue destruction
3. Attempts at healing
4. Involves the adaptive immunity (a specific immune response).

Question 9

Describe the patterns of chronic inflammation

Answer 9

Granulomas
Ulcers
Serous and Fibrinous
Suppuration

Question 10

describe the formation of granulomas

Answer 10

a collection of macrophages/leukocytes.
Occur in chronic inflammation.
core = necrosis (collection of dead cells), macrophages surround this and T cells then surround the macrophages.

Question 11

What key cells are involved in adaptive immunity and how do they work

Answer 11

Adaptive immunity = Chronic inflammation.
T Lymphocytes
- Th (helper) - tag the pathogen which alerts other immune cells that it needs to be killed
-Tc (cytooxic) - Degrade and engulf the pathogen
B lymphocytes
- Plasma cells - produce antibodies which attach are are specific to a pathogen and will only bind to one type of antigen.

Question 12

List other mediators involved in the adaptive immune response

Answer 12

Monocytes/macrophages (leukocytes)
Interleukins
Acute phase proteins
complement proteins

Question 13

Which cell type is responsive to allergies

Answer 13

Basophils

Question 14

Which cell type is responsive to parasites

Answer 14

Eosinophils

Question 15

Which cell type is responsive to acute inflammation/bacteria infection

Answer 15

Neutrophils

Question 16

Which cell type is responsive to chronic inflammation/viral infection

Answer 16

lymphocytes

Question 17

Describe the formation of Ulcers

Answer 17

A break in the epithelial surface
Can occur in acute or chronic inflammation

Question 18

What feature would you see in a chronic ulcer that you wouldn’t see in an acute ulcer

Answer 18

Vascular and fibrovascular granulation tissue. This is evidence of regeneration

Question 19

Serous inflammation is found when

Answer 19

accumulation of fluid in acute inflammation

Question 20

Fibrinous inflammation is found when

Answer 20

Accumulation of fluid in chronic inflammation

Question 21

What are the key macroscopic features of Crohns Disease

Answer 21

Can effect whole GI tract
Bowel inflamed, ulcers and fissures
Cobblestoning (alternating inflammation and ulceration)
Fistulae (passage from one epithelial lining surface to another)
Abscesses (accumulation of pus in tissue)

Question 22

What are the key microscopic features of Crohns Disease

Answer 22

Transmural inflammation
Patchy, skip lesions
Chronic inflammatory cells predominate (lymphocytes)
Granulomas

Question 23

What are the key macroscopic features of Ulcerative Colitis

Answer 23

Affects only the colon (large bowel)
Ulceration
Pseudopolyps (outpouching of normal mucosa)