Acute Inflammation 1 Flashcards
Name 6 causes of acute inflammation.
1) Pathogen
2) Mechanical - trauma or injury
3) chemical - upset Ph etc.
4) Physical - eg. extreme conditions
5) cell necrosis
6) hypersensitivity
What localises the acute inflammation process?
Plasma proteins
Is the response rapid, or slow?
Rapid
What helps protect the site?
Cardinal signs and loss of function.
How are neutrophils and macrophages involved in acute inflammation?
Neutrophils destroy pathogens and denature antigens. Macrophages clear debris, and display the antigens.
What are local effects of acute inflammation?
Redness, pain, swelling, heat, loss of function
What is another word for swelling
tumor
What does rubor mean?
redness
What does calor mean?
heat
What does dolar mean?
pain
What is exudate?
Fluid rich in proteins, plasma, immunoglobins, fibrinogen, neutrophils.
Due to acute inflammation, the vessel’s radius flow changes. This causes the permeability of the vessel wall to change. What then leaks out of the vessel to the extravascular space?
Exudate - causes oedema
Neutrophils too!
During acute inflammation, the first of a sequence is the arteriole constricts quickly. (transient arteriolar constriction). What happens after this?
2) Local arteriolar dilation. (arterioles widen)
3) Smooth muscle relaxes
This increases local tissue blood flow.
If there is less fluid in the vessel, this means that there is an increased viscosity (thickness) within the vessel…what does this lead too.
Increased viscosity
Changes in flow
Causes neutrophils to go to the outside edge of the vessel - margination
They then leave the vessel emigration.
Where does the process of acute inflammation occur?
In the microcirculation.
What is the microcirculation?
The capillaries - between the venules and the arterioles. Also the extracellular space around these, and the lympathic channels.
what is normal laminar flow like?
WBCs surrounded by RBCs.
What is pavementing?
Neutrophils adhering to the endothelium .
what are the immediate systematic effects of acute inflammation?
Pyrexia - raised temperature
Malaise, nausea, (abdominal pain and vomiting in children)
Neutrophilia - raised WBC count
What can be some long term effects of acute inflammation?
regional lymph node enlargement
weight loss
Anaemia
what can be some complications of acute inflammation?
chronic inflammation
Granulation tissue
Scar formations
Where may mediators of acute inflammation be found?
released from cells
in plasma
on endothelial cell surfaces
name a cell surface mediator and say what it does.
ICAM 1 - helps neutrophils stick
Histamine is a mediator released from the cell. What does it do?
vasodilation, increased permeability
Serotonin is a mediator released from a cell. What does it do?
vasoconstriction
What do prostaglandins do?
Promote histamines effects, inhibit inflammation
What do leukotrienes do?
they are vasoactive - they increase vessel permeability and dilate smooth muscles
what does omega - 3 polyunsaturated fatty acids do?
decrease prostaglandins
what is PAF and what does it do?
platelet activating factor. reduces permeability, enhances platelets
What do cytokines and chemokines do?
attract inflammatory cells
give some examples of oxygen free radicals and say what they do
H2 O2 OH -
Amplify other mediators effects
What does nitric oxide do?
Regulates smooth muscle, anti-platelet
In plasma, what do blood coagulation pathways do?
clot fibrinogen in exudate
in plasma, what does fibrinolysis do?
breaks down fibrin to produce vasoactive products. Helps maintain the blood supply.
in plasma, what does bradykinin do?
pain
in plasma, what does complement activation do?
ties the inflammatory response with the immune response. stimulates phagocytosis and chemotaxis etc.
How can acute inflammation alter the detriment of the patient
could spread to blood stream - sepsis
bacteraemia
septicaemia
toxaemia
could cause toxic shock syndrome.
What would inflammation of the meninges be called? (think - any structure = itis)
meningitis
what is infection of the lungs called?
pneumonia
what is infection of the plural cavity called?
pleurisy
describe the pathway of a neutrophil.
neutrophil - mobile phagocyte
neutrophil -> chemotaxis -> adhere -> release granules -> kills cell -> neutrophil dies -> produces pus
what is an abscess?
a collection of pus (suppuration) under pressure from internal
what is a multilocated abscess?
when the pus bursts through the abscess inside and forms new cavities
