Chronic Inflammation

Question 1

What is the difference in the immune systems involved in acute and chronic inflammation?

Answer 1

Acute inflammation involves only innate immunity

Chronic inflammation involves innate and adaptive immunity

Question 2

How long does acute inflammation last?

Answer 2

Hours to days

The response is very rapid and short-lived

Question 3

How do the blood vessels change in acute inflammation?

Answer 3

Blood vessels dilate and increase in permeability

This allows an increased blood flow into the area

Question 4

What is the name of the process where fluid leaks out of blood vessels in acute inflammation?

Answer 4

Fluid exudation

The fluid is rich in proteins e.g. Igs, fibrinogen

Question 5

What are the main cells involved in an acute inflammatory response?

Answer 5

1. neutrophils
2. mast cells
3. macrophages

Question 6

What are the 4 terms (latin) used to characterise the symptoms of acute inflammation?

Answer 6

1. rubor - redness
2. calor - heat
3. tumor - swelling
4. dolor - pain

Question 7

What are the stages involved in resolution of acute inflammation?

Answer 7

1. phagocytosis of the insulting agent
2. fibrinolysis
3. phagocytosis of debris

Question 8

What is involved in fibrinolysis?

Answer 8

fibrin leaks out of the blood vessels and forms fibrinogen

fibrinolysis is the breaking down of the fibrin

Question 9

What is meant by organisation in repair after acute inflammation?

Answer 9

Replacement of damaged tissue by granulation tissue

Question 10

What are the main cells that phagocytose cell debris after resolution of acute inflammation?

Answer 10

macrophages

Question 11

When does repair occur after acute inflammation, opposed to resolution?

Answer 11

When there is too much damage to a tissue that it can’t be repaired

Some tissues are unable to regenerate and replace lost cells

Question 12

What is the role of granulation tissue?

Answer 12

It allows new blood vessels to form

It contains fibroblast cells that deposit collagen to form the fibrous scar

Question 13

How long does chronic inflammation last for?

Answer 13

Weeks, months, years

It has a slow onset and a longer duration

Question 14

What are the 2 processes in chronic inflammation that involve granulation tissue?

Answer 14

1. angiogenesis

2. fibrosis

Question 15

What is angiogenesis?

Answer 15

Development of new blood vessels

Question 16

What is fibrosis?

Answer 16

Laying down of collagen that will go on to form the fibrous scar

Question 17

What cells are involved in chronic inflammation that are not involved in acute inflammation?

Answer 17

1. lymphocytes
2. plasma cells

(also more macrophages are involved)

Question 18

What are the 3 main conditions that are secondary to chronic inflammation?

Answer 18

1. amyloidosis
2. cachexia
3. anaemia of chronic disease

Question 19

What is amyloidosis?

Answer 19

Proteins misfold and form aggregates that are deposited around the body

they can cause damage to the tissues that they are deposited in

Question 20

What is cachexia?

Answer 20

When a patient appears emaciated and thin

Question 21

What causes anaemia of chronic disease?

Answer 21

cytokines reduce the amount of erythropoietin produced

red blood cell production decreases

cytokines affect iron production around the body, producing mild anaemia

Question 22

What are the main chemicals involved in cachexia, anaemia of chronic disease and amyloidosis?

Answer 22

cytokines produced in chronic inflammation

Question 23

What is meant by concomitant tissue destruction and repair?

Answer 23

Both tissue destruction and repair are happening at the same time

Question 24

What are the types of cells involved in chronic inflammation?

Answer 24

mononuclear cells - single round nucleus

Question 25

Under what circumstances may acute inflammation lead to chronic inflammation?

Answer 25

1. if acute inflammation is not resolved | 2. if there are frequent recurrent episodes of acute inflammation

Question 26

What are examples of conditions that can cause acute inflammation to progress to chronic inflammation?

Answer 26

1. if helicobacter pylori causing acute gastritis is not treated 2. from chronic cholecystitis -inflammation of the gall bladder

Question 27

What are the other causes of acute inflammation?

Answer 27

1. persistent infection by certain microorganisms 2. prolonged exposure to potentially toxic agents 3. autoimmunity 4. unknown

Question 28

Why do certain microorganisms cause chronic inflammation?

Answer 28

the macrophages find it difficult to remove all the bacteria

Question 29

What is meant by endogenous and exogenous toxic agents?

Answer 29

endogenous factors come from within the body exogenous factors are external stimuli

Question 30

What is an example of an endogenous toxic agent that can cause chronic inflammation?

Answer 30

a splintered segment of bone that is difficult to break down

Question 31

What is an example of an exogenous toxic agent that can cause chronic inflammation?

Answer 31

asbestos fibres sutures

Question 32

Why are autoimmune diseases an example of chronic inflammation?

Answer 32

The body is having an immune reaction to its own antigens which is persistent and ongoing

Question 33

What are the 3 unknown factors that cause chronic inflammation?

Answer 33

1. crohn's disease 2. ulcerative colitis 3. sarcoidosis

Question 34

What is chronic pyelonephritis?

Answer 34

chronic inflammation affecting the kidney

Question 35

What life-threatening consequence can chronic ulcers in the stomach lead to?

Answer 35

Perforations these are holes going through the lining of the stomach that are caused by inflammation destroying the overlying tissue

Question 36

What causes liver cirrhosis?

Answer 36

prolonged exposure to toxic agents e.g. alcohol, high lipid levels, hepatitis viruses

Question 37

What happens in liver cirrhosis?

Answer 37

1. underlying liver tissue is destroyed 2. it tries to regenerate, leading to nodules 3. deposition of collagen in the liver leads to a shrunken liver with poor function

Question 38

What causes interstitial fibrosis?

Answer 38

asbestos bodies entering the alveoli in the lungs

Question 39

What happens in interstitial fibrosis?

Answer 39

the alveolar walls thicken which interferes with gas exchange

Question 40

What happens in lupus nephritis?

Answer 40

The kidney becomes shrunken and granular The glomerulus is replaced by collagen and no longer functions

Question 41

What causes cells to become involved in the inflammatory response?

Answer 41

cytokines cause cells and proteins in the blood vessels to emigrate out of the vessels and towards the sites of injury

Question 42

Where do macrophages originate? What are they called when they are in the blood and tissue?

Answer 42

originate in the bone marrow in the blood, they are monocytes when they enter tissue, they are macrophages

Question 43

What are macrophages called in the CNS, liver, bone and lungs?

Answer 43

CNS - microglia Liver - Kupffer cells Bone - osteoclasts Lung - alveolar macrophages

Question 44

What causes the macrophages to become activated? What signals do they produce?

Answer 44

they are activated in response to cytokines from t cells they ingest agents by phagocytosis and then produce signals to the fibroblasts, b cells and t cells

Question 45

What does a plasma cell look like? What does it do?

Answer 45

it has a clock-faced nucleus with speckles it is a form of b cell that produces antibodies

Question 46

What do fibroblasts look like? What do they do?

Answer 46

they are long, thin cells that produce collagen they are responsible for forming scars

Question 47

When will eosinophils and mast cells be involved in the chronic inflammatory response?

Answer 47

eosinophils and mast cells are activated by IgE If there is a type of chronic inflammation involving IgE

Question 48

What is involved in the cycle of chronic inflammation?

Answer 48

1. macrophages follow chemokines to the injured area 2. macrophage is activated in the tissue, produces cytokines and presents antigens to t cells 3. t cells are activated and go on to activate b cells 4. b cells become plasma cells and release antibodies 5. inflammatory mediators from the t cells can activate more macrophages

Question 49

How can macrophages cause tissue injury and damage?

Answer 49

they release reactive oxygen species and enzymes

Question 50

What are the 2 roles of granulation tissue?

Answer 50

1. angiogenesis is the formation of new blood vessels | 2. fibroblasts are involved in collagen deposition

Question 51

When looking at chronic inflammation under the microscope, what is significant about what is seen?

Answer 51

1. angiogenesis means that there are many blood vessels visible 2. inflammatory cells - especially lymphocytes

Question 52

What is a granuloma?

Answer 52

a collection of activated epitheloid macrophages

Question 53

What does epitheloid mean?

Answer 53

looks like epithelial cells

Question 54

What does a granuloma look like under the microscope?

Answer 54

pink cytoplasm, indistinct cell membranes, oval nucleus

Question 55

What are the epitheloid macrophages in a granuloma surrounded by?

Answer 55

mononuclear leucocytes (b cells and t cells) and occasionally some plasma cells

Question 56

What are the 2 types of granulomatous inflammation?

Answer 56

1. caseating | 2. non-caseating

Question 57

What is significant about the appearance of a caseating granuloma?

Answer 57

when cutting into the granuloma, any area looks like cream cheese

Question 58

What is the difference between a caseating and non-caseating granuloma?

Answer 58

in a caseating granuloma, the cells in the centre are necrotic in a non-caseating granuloma, the cells in the centre are not dead

Question 59

What infection commonly causes a caseating granuloma?

Answer 59

tuberculosis

Question 60

What other type of cells are often found in granulomatous inflammation?

Answer 60

multinucleate giant cells

Question 61

What are multinucleate giant cells?

Answer 61

many macrophages merge together to form a giant cell

Question 62

Why is it important to be able to identify a granuloma?

Answer 62

There are only a limited number of conditions that cause granulomatous inflammation Identifying it informs further tests

Question 63

What are the 6 categories that cause granulomatous inflammation?

Answer 63

1. bacterial 2. parasitic 3. fungal 4. inorganic metals or dust 5. foreign bodies 6. unknown

Question 64

What are common bacterial infections that cause granulomatous inflammation?

Answer 64

1. tuberculosis 2. leprosy 3. syphilis 4. cat-scratch

Question 65

What are common parasitic and fungal infections that cause granulomatous inflammation?

Answer 65

parasitic - schistosomiasis fungal - histoplasma, cryptococcus

Question 66

What are examples of inorganic metals/dust or foreign bodies that cause granulomatous inflammation?

Answer 66

inorganic metals - silicosis, beryliosis foreign body - sutures, vascular grafts

Question 67

What conditions cause unknown granulomatous inflammation?

Answer 67

sarcoidosis and ulcerative colitis