2,193 bytes added
, 11:11, 4 August 2010
===Functions of Exudate===
# Dilutes the toxic agent, reducing its effect upon the tissue cells.
# The protein components may contain antibodies which attack or coat (opsonise) the irritant.
#* This makes the irritant more digestible to neutrophils and macrophages.
# Exudates may contain fibrin.
#* This is very sticky - immobilises the irritant.
#* Provides a framework over which the leukocytes crawl to reach the irritant.
#* Fibrin is also chemotactic to neutrophils, bringing more of these cells into the injured area.
# Exudate on a suface will wash away the irritant.
#* E.g the skin and alimentary track.
# Brings the irritant to the lymph nodes, via the lymphatics, for further processing or antigen presentation.
#* Preferably within white blood cells such as macrophages and neutrophils.
#* Local lymph nodes may also be inflamed following inflammation of a tissue which drains into them.
===Sequelae to Exudation===
* Catarrhal and serous exudationresolve when the irritant is overcome.
** Alternatively, they may progress to a more serious reaction.
* Fibrinous exudates may also resolve if the fibrin is digested by macrophages.
** In the pleural and peritoneal cavities, the fibrin may become rganised into fibrous tissue, producing adhesions between the visceral surface.
* Diphtheritic inflammation will only repair by scar formation.
* If haemorrhagic lesions are widespread, they most commonly associated with acute deaths.
** For example in acute viral, bacterial or toxic diseases.
* If the exudation is strictly localised, for example in brusing, then repair may occur.
* The resolution of abscesses depends upon their location.
** If the abscess is near to a surface it will rupture onto it.
** This is beneficial in the skin where it discharges to the exterior, hopefully getting rid of the pyogenic organism.
** If the abscess is in deeper tissues, there is extensive fibrous capsule formation.
*** The fluid becomes inspissated due to withdrawal of water content.
*** Macrophages digest the necrotic remains.
*** Fibrous tissue organises the interior.
*** The very end result is a fibrous scar.
[[Category:Acute Inflammation]][[Category:To Do - Blood]]