PP 3 Chronic Inflamamtion

Question 1

Define chronic inflammation

Answer 1

Prolonged inflammation with associated repair

Question 2

Features of chronic inflammation

Answer 2

• delayed onset
• variable duration
• variable appearances
• limits damage + initiates repair
• can cause debilitating symptoms

Question 3

Ways chronic inflammation can arise

Answer 3

• takes over from acute inflammation
• develops alongside acute inflammation
• arrives de novo: without preceding acute inflammation

Question 4

Examples of chronic conditions which arise de novo

Answer 4

Rheumatoid arthritis
Inflammatory bowel disease

Question 5

Macrophage naming

Answer 5

In circulation- monocyte
After entering tissue- macrophage/histiocyte

Question 6

Describe macrophage

Answer 6

Large cell
Abundant foamy cytoplasm

Question 7

Macrophage functions

Answer 7

• phagocytosis: -removal of pathogens and debris
  -antigen presentation
• synthesis of cytokines + clotting factors
• control other cells by cytokine release

Question 8

Describe a lymphocyte

Answer 8

Small cell
Large spherical nucleus
Thin rim of cytoplasm

Question 9

Two types of lymphocytes

Answer 9

T cells
B cells

Question 10

T cell functions

Answer 10

• helper T cell: assist other inflammatory cells
• cytotoxic T cell: destroys pathogen

Question 11

B cell function

Answer 11

Neutralises pathogens
Mature into plasma cells > produce antibodies

Question 12

Describe a plasma cell

Answer 12

• Eccentric nucleus
• ‘Clock face’ chromatin
• Peri-nuclear clearing (Golgi)- pale space around nucleus

Question 13

Plasma cell function

Answer 13

Produce antibodies

Question 14

Describe an eosinophil

Answer 14

Bi-lobed nucleus
Granular cytoplasm - stains red

Question 15

Eosinophil function

Answer 15

Release variety of mediators
In parasitic infections
In hypersensitivity reactions - allergic reactions

Question 16

Fibroblast/myofibroblast function

Answer 16

Regeneration and repair
Lay down collagen&raquo_space; scar production

Myofibroblasts - contract and close wound

Question 17

Describe giant cells

Answer 17

Multinucleated cell
Fusion of multiple macrophages due to ‘frustrated phagocytosis’

Question 18

Types of giant cells

Answer 18

Foreign body
Langhans
Touton

Question 19

Describe foreign body giant cell

Answer 19

Nuclei randomly assorted

Question 20

Describe Langhans giant cell

Answer 20

Nuclei in rim round edge
Full or partial

Question 21

Describe a Touton giant cell

Answer 21

Nuclei in ring in middle

Question 22

What cells are mainly in RA?

Answer 22

Plasma cells

Question 23

What cells are mainly in chronic gastritis?

Answer 23

Lymphocytes

Question 24

What cells are mainly in Whipple’s disease?

Answer 24

Macrophages

Question 25

Effects of chronic inflammation

Answer 25

- fibrosis - impaired function - increased function (rare) - atrophy - stimulation of immune system

Question 26

Examples of conditions which show the fibrotic effect of chronic inflammation and info

Answer 26

**Acute cholecystitis** - repeated obstruction of bile duct by gall stone - repeated bouts of acute inflammation > chronic inflammation - fibrosis of gall bladder wall **Liver cirrhosis** - chronic damage > fibrosis > scarring > contraction > portal blood flow impaired > portal hypertension > ascites

Question 27

Examples of conditions which show loss of function due to chronic inflammation and info

Answer 27

Idiopathic inflammatory bowel disease: **Crohn’s disease and Ulcerative colitis** - abnormal pain - altered bowl motion - weight loss - rectal bleeding

Question 28

What effects of chronic inflammation does cirrhosis show?

Answer 28

Fibrosis Impaired function

Question 29

Causes of cirrhosis

Answer 29

Alcohol Hepatitis Drugs and toxins Fatty liver disease

Question 30

What is a granuloma?

Answer 30

Epithelial histiocyte with surrounding lymphocytes

Question 31

What is an epithelioid histiocyte?

Answer 31

Macrophage that look like epithelial cells

Question 32

Types of granuloma

Answer 32

- **foreign body**: - destruction + removal of foreign material (not antigenic) - few lymphocytes - **immune mediated**: - destruction + removal of pathogens in response to bacteria/fungi (antigenic) - can be idiopathic - can undergo central necrosis - many lymphocytes

Question 33

Why is mycobacterium difficult to destroy?

Answer 33

Mycolic acids Thick cell wall - macrophage resistant

Question 34

What can mycobacterium cause?

Answer 34

TB - mycobacterium tuberculosis Leprosy - mycobacterium leprae

Question 35

What do granulomas look like on H+E stain and why?

Answer 35

Pink Many macrophages which have an abundant cytoplasm - stains pink

Question 36

What are granulomas with central necrosis characteristic of?

Answer 36

Rheumatoid arthritis

Question 37

Colour of granuloma with central necrosis

Answer 37

Central necrosis is pink

Question 38

What is sarcoidosis?

Answer 38

A disease characterised by the growth of granulomas

Question 39

Where is sarcoidosis often found?

Answer 39

Lungs Lymph nodes

Question 40

Is sarcoidosis necrotising or not?

Answer 40

No necrosis

Question 41

Colour of healthy lymph nodes on H+E stain

Answer 41

Purple Many lymphocytes which have a large nucleus (haematoxylin stains nucleus purple) + thin cytoplasm

Question 42

What condition are Langhans giant cells often seen in?

Answer 42

Tuberculosis

Question 43

What condition are Touton giant cells often seen in?

Answer 43

Fat necrosis Xanthomas

Question 44

What condition are Foreign body giant cells often seen in?

Answer 44

When macrophage is unable to phagocytose foreign body

Question 45

When are granulomas formed?

Answer 45

When there are particles which are difficult to break down but need to be isolated and contained *e..g splinters, mycobacterium tuberculosis*

Question 46

What are epithelioid cells?

Answer 46

Macrophages which have been modified due to increased activity so look like epithelium

Question 47

What are the most common cell types in chronic inflammation?

Answer 47

Macrophages Lymphocytes

Question 48

What is chronic gastritis?

Answer 48

Inflammation of stomach lining most often due to Helicobacter pylori

Question 49

What is an ulcer?

Answer 49

A breach in the mucosa to the level of submucosal layer

Question 50

What is a Mantoux test?

Answer 50

A screening test for TB

Question 51

Describe what happens when a person inhales mycobacterium tuberculosis

Answer 51

- MTB endocytosed by macrophages - MTB replicates within phagosome - MTB proliferates in alveolar macrophages + air spaces - bacteraemia develops - T helper cell response activates macrophages >> produce TNF - monocytes differentiate into epithelioid histiocyte >> granulomas - illness contained