Inflammation Flashcards
Define inflammation
Reactions of living vascularised tissue to sub-lethal injury
What are the three types of inflammation?
Acute
Chronic
Granulomatous (type of chronic inflammation)
What are the five cardinal signs of inflammation?
Rubor Dolor Calor Tumor Functio Laesa
What triggers histamine release and what effect do histamines have?
Binding of IgE to the Fc receptor on mast cells Antigens bind to the IgE and cause cross-linking and mast cell degranulation Histamines cause: vasodilation + increased vascular permeability
What is an exudate?
Fluid with high protein content and cellular debris, which leaves vessels and deposits in tissues or on tissue surfaces, usually as a result of inflammation
What is a transudate?
Fluid escape from vessels due to disturbances in hydrostatic and colloid osmotic pressure – NOT CAUSED BY INFLAMMATION
What is the most important difference between exudates and transudates?
Exudates are associated with inflammation transudates are not
What are the three types of exudates and how do they differ?
Serous – fluid filled – lowest protein content of the three exudates Fibrinous – high fibrin content – more due to traumatic injury Purulent – pus filled – fibrin, inflammatory cells, debris and fluid
What is the main histological feature of acute inflammation?
Lots of neutrophils
What are the three main cell types involved in chronic inflammation?
Macrophages
Lymphocytes
Plasma Cells
What is an important difference between acute and chronic inflammation?
Acute inflammation produces an exudate whereas chronic inflammation doesn’t
What are the histological features of granulomatous inflammation?
Granuloma – collection of macrophages
You get a collection of macrophages in the middle and they may appear to have fused together
There will be lymphocytes and plasma cells around the outside
What is the good outcome of inflammation?
Resolution – healing of tissue damage to preserve integrity and function
What is ‘Repair’ in terms of wound healing?
Replacing normal tissue with scar tissue
Give an example of resolution and how it takes place.
Pneumococcul lobar pneumonia
Inititally you get exudation
Then you get red hepatisation (erythrocytes move into the alveolar cells)
Grey hepatisation – erythrocytes break down
Provided the basement membrane is still there – the body can remove the problem
