Chronic Inflammation

Question 1

Define chronic inflammaiton

Answer 1

Inflammation in which cell population is especially

Lymphocytes
Plasma cells
Macrophages

Question 2

What are the features of chronic inflmmation?

Answer 2

Tissue or organ damage, necrosis, loss of function

Question 3

What are the features of healling and repair in chronic inflammation?

Answer 3

Granulation tissue, scarring and fibrosis

Question 4

What is granulation tissue?

Answer 4

Vascularized tissue that forms as chronic inflammation evolves.

Characterized by presence and proliferation of fibroblasts, keratinocytes, endothelial cells, new thin-walled capillaries, and inflammatory cell infiltration of the extracellular matrix.

Question 5

What can cause chronic inflammation?

Answer 5

May follow from acute inflammation
Arises as primary pathology

Question 6

What are the clinical findings in chronic inflammation?

Answer 6

No specific sore area
Malaise and weight loss
Loss of function

Question 7

What is an example of loss of function due to chronic inflammation?

Answer 7

Crohn’s disease (GI tract ulceration and fibrosis) – pain, diarrhoea, gut obstruction

Question 8

What is characteristic of organisation in acute inflammation?

Answer 8

Granulation tissue - healing and repair, leads to fibrosis and formation of a scar

Question 9

What is the granulation tissue mechanism?

Answer 9

Capillaries grow into an inflammatory mass

Access of plasma proteins

Macrophages from blood and tissue

Fibroblasts lay down collagen to repair damaged tissue

Collagen replaces inflammatory exudate

Question 10

What is the function of granulation?

Answer 10

Patches tissue defects
Replaces dead or necrotic tissue
Contracts and pulls together

Question 11

What are the products of granulation tissue?

Answer 11

Fibrous tissue - scar
Can progress to chronic inflammation

Question 12

What is the most likely cause of primary chronic inflammation?

Answer 12

Autoimmune disease

Question 13

How does Autoimmune disease result in chronic inflammation?

Answer 13

Autoantibodies directed against own cell and tissue components - autoantigens

They damage or destroy organs, tissues, cells, cel components

Question 14

What types of cells does primary chronic inflammation use?

Answer 14

Lymphocytes, plasma cells, macrophages, fibrosis

Question 15

What are the other common methods of triggering a chronic inflammatory response?

Answer 15

Material resistant to digestion : mycobacteria, Brucella, viruses, this is because their cell wall is resistant to enzymes

Exogenous substances:
sutures, metal and plastic eg joint replacements, mineral crystals, glass

Endogenous substances: Necrotic tissue, keratin, hair, none of which can easily be phagocytosed

Granulomatous inflammation is common

Question 16

What are lymphocytes responsible for?

Answer 16

B cells and T cells

Immune response
Immune memory

Question 17

What is a plasma cell?

Answer 17

Differentiated B cells, differentiated to produce antibodies

Question 18

What do NK cells do?

Answer 18

Destroy antigens and cells, granule proteins like T cells

Question 19

Which is longer lived, macrophages or neutrophils?

Answer 19

Macrophages, they take over from neutrophils

Question 20

What might macrophages produce?

Answer 20

Interferons and other chemicals, used to destroy

Question 21

What are fibroblasts?

Answer 21

Motile cells which are metabollically active, they make and assemble structural proteins, including collagens

Question 22

Where do fibroblasts originate from?

Answer 22

From the embryonic mesoderm tissue, and they are not terminally differentiated.

Question 23

What is the outcome of chronic inflammation?

Answer 23

Ongoing tissue damage and destruction,

insidious loss of function

Granulation tissue, angiogenesis

Scarring and fibrosis

Granuloma formation

Question 24

What is angiogenesis?

Answer 24

Angiogenesis is the formation of new blood vessels.

Question 25

How does angiogenesis play a role in granulation tissue?

Answer 25

New vessels form- capillary buds Vascular Endothelial Growth Factor (VEGF) released by hypoxic cells stimulates proliferation Enzyme secretion aids process Enable blood supply to enter damaged tissue

Question 26

Discuss angiogenesis and organisation in thrombosis

Answer 26

Limits thrombus propagation Reinstatement of flow

Question 27

Discuss angiogenesis in malignant tumours

Answer 27

Angiogenesis occurs as tumour grows Potential for therapeutic control

Question 28

What is granulomatous inflammation always characterised by?

Answer 28

Granulomas (granulomata) in tissues and organs

Question 29

How is Granulomatous inflammation stimulated?

Answer 29

Stimulated by indigestible antigen, body cannot get rid of it

Question 30

What are idiopathic diseases?

Answer 30

Diseases which we don't know why they happened.

Question 31

How are granulomas formed?

Answer 31

Aggregates of epithelioid macrophages in tissue

Question 32

What is epitheliod?

Answer 32

Looks like epithelial

Question 33

What might granulomas surround?

Answer 33

Giant cells, dead material

Question 34

What might granulomas be surrounded by?

Answer 34

Lymphocytes

Question 35

What do granulomas contain?

Answer 35

Neutrophils, eosinophils

Question 36

Granulomas are formed as a result of?

Answer 36

Response to indigestible antigen Many are type 4 hypersensitivity reactions

Question 37

What do giant cells consist of?

Answer 37

A giant cell is a mass formed by the union of several distinct cells (usually macrophages)

Question 38

Describe the structure of a giant cell

Answer 38

Large cytoplasm; multiple nuclei - several types

Question 39

Are there always granuloma for giant cells to be present?

Answer 39

No

Question 40

Name a type of giant cell

Answer 40

Langhans type

Question 41

What is a Langhans type giant cell classically found in?

Answer 41

TB

Question 42

Describe the structure of Langhans type

Answer 42

Peripheral rim of nuclei Large eosinophilic cytoplasm

Question 43

What is the giant cell often associated with pyogenic granulation tissue?

Answer 43

Foreign body type Acutely inflamed neutrophils, pus organisation giant cells

Question 44

What type of giant cell might you see with a ruptured silicone implant? e.g breast implant

Answer 44

Silicone associated giant cells Vacuoles contain leaked silicone

Question 45

Name some Infectious granulomatous diseases

Answer 45

Tuberculosis (Mycobacterium tuberculosis), Leprosy Mycobacterium leprae Syphilis

Question 46

Describe Caseous necrosis

Answer 46

Cell death in which the tissue maintains a cheese-like appearance. Dead tissue appears as a soft and white proteinaceous dead cell mass. Dead tissue surrounded by macrophages, giant cells, lymphocytes

Question 47

Give examples of Non-infective granulomas

Answer 47

Rheumatoid disease - tissue specific auto-immune disease Sarcoidosis - Development of granulomas within organs of the body Crohn’s disease – chronic inflammatory bowel disease

Question 48

What are the common processes in chronic inflammation?

Answer 48

Acute inflammation Granulation tissue formation Local angiogenesis - new vessels grow Fibrosis and scar formation

Question 49

What is surgical wound healing?

Answer 49

Healing by primary intention

Question 50

What are the goals of surgical wound healing?

Answer 50

Minimal gap, small amount of granulation tissue, small linear scar

Question 51

What is healing of larger defects?

Answer 51

Healing by secondary intention

Question 52

Describe the granulation tissue ingrowth in larger defects

Answer 52

Lots of it Contraction and scarring

Question 53

What is the sequence of events in wound healing?

Answer 53

- injury, blood clot, acute inflammation, fibrin - many growth factors and cytokines involved -granulation tissue growth - angiogenesis - phagocytosis of fibrin - myofibroblasts move in and lay down collagen - contraction of scar - re-epithelialisation

Question 54

What conditions favour wound healing?

Answer 54

Cleanliness Apposition of edges (no haematoma) Sound nutrition Metabolic stability and normality Normal inflammatory and coagulation mechanisms Note local mediators

Question 55

What conditions result in impaired wound healing?

Answer 55

Dirty, gaping wound, large haematoma Poorly nourished, lack of vitamins C, A Abnormal CHO metabolism, diabetes, corticosteroid therapy Inhibition of angiogenesis

Question 56

What is the sequence of events in fracture healing?

Answer 56

Trauma, fracture, haematoma Bits of dead bone and soft tissue Acute inflammation, organisation, granulation tissue, macrophages remove debris Granulation tissue contains osteoblasts as well as fibroblasts

Question 57

What are the stages of callus formation?

Answer 57

Osteoblasts lay down woven bone Nodules of cartilage present Followed by bone remodelling: osteoclasts remove dead bone progressive replacement of woven bone by lamellar bone reformation of cortical and trabecular bone

Question 58

What stimulates proliferation of vessels?

Answer 58

Vascular endothelial growth factor, released by hypoxic cells, stimulates proliferation

Question 59

What aids the process of angiogenesis?

Answer 59

Enzyme secretion

Question 60

What is the benefit of angiogenesis?

Answer 60

Allows blood supply to enter damaged tissue