CSIM 1.48-49 Inflam & Repair 1 & 2

Question 1

Describe acute inflammation

Answer 1

24-48 hours

Causes varied - cellular injury, microbial infection, physical damage, necrosis, hypersensitivity

Rubor, calor, tumor, dolor
Redness, heat, swelling, pain.

Clinical features- fever, swelling, pain, heat, raised ESR/CRP/WBC

Question 2

Describe the mechanism of inflammation on a cellular level

Answer 2

Vascular dilation - increased blood flow

Increased vascular permeability - swelling

Leukocyte migration - neutrophilic infiltration “chemotaxis”

Increased lymphatic flow - clear fluids, dilute toxins and carry antigens to lymph nodes

Question 3

Explain chemotaxis

Answer 3

Neutrophils regularly circulate in the blood. When inflammation occurs, chemotaxins are found in the area of inflammation, this causes “margination” of neutrophils to the endothelium of the vessel. The neutrophils then procede to adhere themselves to the endothelium and begin the process of migration where the cells squeeze through the endothelial cells to gain entry to the site.

This process is mediated by selectin and other chemotaxins.

Question 4

List 4 possible sequelae in inflammation

Answer 4

Resolution
Repair
Suppuration
Chronic inflammation

Question 5

What is suppuration? Possible sequelae of suppuration

Answer 5

Formation of pus.
Pus is a yellow viscous fluid that is filled with cellular debris from the immune response against the infection. It consist of DNA, protein, neutrophils.

Reabsorption, abscess formation or empyema.

Question 6

Describe the basic process of wound healing/reparation

Answer 6

Repair is done by replacing specialised tissue with fibrous tissue. The processes is called granulation tissue formation.

These cells work together to remove debris, angiogenesis, produce extracellular matrix to patch up the damage which then turns into fibrous tissue. Wound repair also involves contraction which pulled the two sides together to close the wound (myofibroblast)

Question 7

4 cells involved in wound repair

Answer 7

Endothelial cells, myofibroblast, fibroblasts and macrophages

Question 8

What mediates repair?

Answer 8

Growth factors e.g. Endothelium-growth factor, vascular endotheliual growth factor.

Question 9

Complications of wound repair

Answer 9

Stricture/narrowing
Keloid
Impaired mobility

Question 10

What can affect the repair of a wound?

Answer 10

Infection
Ischaemia
Movement
Nutrition/age
Steroid
De-nervation

Question 11

List some pro-inflammatory cytokines

Answer 11

IL-1
IL-6
IL-12
IL-17
IL-18
TNF-alpha
IFN-gamma

Question 12

List some anti-inflammatory cytokines

Answer 12

IL-4
IL-10
IL-11
IL-13
TGF-beta
IFN-alpha

Question 13

Which cytokine causes pyrexia?

Answer 13

Il-1

Question 14

Describe some systemic effects of inflammation

Answer 14

Fever caused by release if IL-1
Raised CRP by the liver
Redirected blood due to autonomic response
Behavioural changes like malaise, rigors and anorexia

Question 15

What are some macroscopic signs of inflammation?

Answer 15

Swelling, suppuration, catarrhal, fibrinous occurances like percarditis.

Question 16

Why is swelling of the brain harmful?

Answer 16

Confined area, raised ICP, compresses brain parts, can cause brain herniation.

Question 17

Describe what a granuloma is

Answer 17

Aggregate of histiocytes +/- lymphocytes
Secretion>phagocytosis
Epitheloid appearance
Can result in fusion of cells, creating giant multi-nucleated cells

Marker of chronic inflammatory disorders

Question 18

Describe
= foreign body granuloma giant cell
= touton giant cell
= langerhans giant cell

Answer 18

= foreign body trapped in the body, hundred of nuclei
= fill with cholesterol/fat, ring of nuclei, e.g. Exthalasma
= TB associated, horse shoe nuclei

Question 19

Describe the some causes of chronic inflammation

Answer 19

Persistent infection
Poorly degradable material e.g. Asbestos
Autoimmune disease

Question 20

Describe some causes of persistent infection

Answer 20

Chronic abscess
Indigestible material like a splinter
Resistant organisms like TB or parasites

Question 21

Macroscopic signs of chronic inflammation

Answer 21

Chronic abscess
Fistula
Sinus
Chronic ulcer
Fibrosis and strictures
Granulamatous inflammation

Question 22

What is a fistula?

Answer 22

Connecting of two epithelial areaz through a conduit e.g. Intestine fistual

Question 23

Some microscopic signs of chronic inflammation

Answer 23

Tissue destruction
Repair (fibrosis/granulation)

Inflammatory cells like lymphocytes, neutrophils, macrophages, plasma cells

Granuloma

Question 24

What is amyloidosis?

Answer 24

Accumulation of starch like extracellular material made of beta pleated sheets of protein called Amyloid

Becomes hard/waxy, resistant to removal

Occurs around blood vessels and skin blisters

Can cause problems in kidney and if in brain -> alzheimer’s

Question 25

Some complications of chronic inflammation

Answer 25

Amyloidosis
Carcinogenesis
Calcification
Hypersensitivty reactions III and IV

Question 26

Describe the role of neutrophils in inflammation

Answer 26

WBC, phagocytosis of pathogen
AKA polymorphs
Hallmark of inflammation, showed up 6-24 hours after

Work by binding opsonised pathogens then phagocytose and lyse them.