Inflammation Flashcards
What are some causes of acute inflammation?
Trauma
Foreign bodies
Immune reactions
Necrosis
How strong will inflammation be in the case of necrosis?
very strong
What happens to blood vessels during inflammation?
They undergo vasodilation
What happens to vascular permeability during inflammation?
The permeability of the endothelium increases as endothelial cells move apart
Which chemicals cause vascular changes during inflammation?
Histamine and nitric oxide
What is caused by vasodilation of the blood vessels?
Heat (Calor)
Erythema (Rubor)
What is erythema?
Redness
What is stasis?
The slowing down of leukocytes due to vasodilation
What is margination?
The movement of leukocytes to the outside of the blood vessel walls
What do selectins on endothelial cells adhere to?
Proteoglycans on white cekks
What do adhesion molecules on endothelial cells bind to?
Integrins on white cells
What occurs due to increased vascular permeability?
Neutrophils move into the tunica intima through diapedesis
Proteins move into the tissue
This decreases water potential in the tissue
Water then moves into the tissue
This causes swelling (Tumor)
What is VEGF?
Vascular Endothelial Growth Factor
What are the effects of VEGF?
Increased vascular permeability
Increased blood supply to the inflamed tissue
What is chemotaxis?
The movement of leukocytes towards a chemical gradient
What are some examples of chemicals that attract white cells?
Bacterial components
C5a
C3a
leukotrienes
Interleukins
How are reactive oxygen species formed?
NADPH oxidase reduces oxygen
This forms a superoxide
This is then converted into Hydrogen peroxide
Which chemicals cause pain in inflammation?
Bradykinin and prostaglandins
What are the 4 outcomes of inflammation?
Resolution
Suppuration
Chronic inflammation
Restitution
What is resolution of inflammation?
The preferred outcome, in which the inflammation reduces with no damage
What factors usually allow for resolution of inflammation to occur?
Shorter lasting inflammation - longer lasting inflammatory responses are less likely to be resolved as foreign bodies will persist and cause damage
Superficial damage - Much easier to resolve if there is a residual framework on which to rebuild
Good blood supply - Healing is an active process so O2 is required for respiration and blood is required for transport of proteins and waste
Which conditions can decrease the likelihood of resolution?
Hypoxia
Anaemia
Liver failure
Malnutrition
What is suppuration?
The formation of pus, usually in the form of an abscess
What is pus formed from?
Dead and damaged macrophages and neutrophils
What is an abscess?
A formation of pus, containing a bacterial colony
Why do abscesses persist?
Abscesses have no blood supply to the centre, so no immune cells can reach the bacterial colony
How are abscesses treated?
Via surgical draining
What is chronic inflammation?
Inflammation caused by a persistent injury or underlying immune cause such as autoimmunity or hypersensitivity
What leukocytes are involved in chronic inflammation?
Lymphocytes and macrophages
What are some examples of conditions caused by mycobacteria?
Tuberculosis
Leprosy
What is a granuloma?
An aggregate of epithelial histiocytes (macrophages) with a leukocyte cuff
What are the 5 main causes of granuloma formation?
Foreign Bodies
Mycobacteria
Parasites
Cancers
Organ specific immune related diseases
What are some examples of some organ specific, immune related diseases that can cause granuloma formation?
Crohn’s, Polyangiitis, Hypersensitivity Pneumonitis
What is found at the centre of a granuloma?
Caseous Necrosis (Cheese-like)
What is the test for mycobacteria in granuloma formation?
Ziehls Neelson Staining
What does Ziehls Neelson Staining test for?
Acid fast Bacilli (Mycobacteria)
What is restitution?
Cessation of inflammation, but with formation of scar tissue (fibrosis) to fill damaged areas
How can cardiac scarring cause damage
It decreases muscle contraction which can lead to heart failure
It can lead to nerve damage, decreasing electrical impulses, which can lead to an arrhythmia
What is scarring of the liver known as?
Cirrhosis
What forms scar tissue?
Collagen fibres and fibroblasts
