Inflammation
Inflammation
Inflammation
Inflammation
complex protective reaction caused by various endo- and exogenous stimuli injurious agents are destroyed, diluted or walled-off without inflammation and mechanism of healing could organism not survive can be potentially harmfull
Terminology
Greek root + -itis metritis, not uteritis kolpitis, not vaginitis nephritis, not renitis
Mechanisms
local - in cases of mild injury systemic 3 major: 1. Alteration 2. exsudation - inflammatory exsudate
liquid (exsudate) cellular (infiltrate)
3. proliferation (formation of granulation and fibrous tissue) usualy - all 3 components - not the same intensity
Process of Inflammation
Functions of Inflammation
1. Destroy and remove pathogens
2. If destruction is not possible, to limit effects by confining the pathogen and its products. 3. Repair and replace tissue damaged by pathogen and its products.
Classification
Length:
acute Chronic
Classification
According to histological features
nonspecific (not possible to trace the etiology) - vast majority specific (e.g. TB)
Acute inflammation
Important role in inflammation has microcirculation! Supply of white blood cells, interleukins, fibrin, etc.
Local symptomatology
Classical 5 symptoms 1. calor - heat 2. rubor - redness 3. tumor - swelling 4. dolor - pain 5. functio laesa - loss (or impairment) of function
Systemic symptomatology
fever (irritation of centre of thermoregulation)
TNF, IL-1 IL-6 high erythrocyte sedimentation rate
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Vascular changes
vasodilation
increased permeability of vessels due to widened intercell. junctions and contraction of endothelial cells (histamin, VEGF, bradykinin)
protein poor transudate (edema) protein rich exudate leukocyte-dependent endothelial injury
proteolysis protein leakage
Cellular events
leukocytes margination rolling adhesion transmigration emigration of:
neutrophils (1-2 days) monocytes (2-3 days)
chemotaxis
endogenous signaling molecules - lymphokines exogenous - toxins
phagocytosis - lysosomal enzymes, free radicals, oxidative burst passive emigration of RBC - no active role in inflamm. - hemorrhagic inflammation
Phagocytosis
Adhesion and invagination into cytoplasm Engulfment Lsosomes destruction In highly virulent microorganisms, leucocytes can die not the microbe In highly resistant microorganisms persistence within macrophage - activation after many years
2. healing by scar
tissue destruction fibrinous inflammtion purulent infl. abscess formation (pus, pyogenic membrane, resorption - pseudoxanthoma cells - weeks to months)
Chronic inflammation
reasons:
persisting infection or prolonged exposure to irritants (intracell. surviving of agents - TBC) repeated acute inflamations (otitis, rhinitis) primary chronic inflammation - low virulence, sterile inflammations (silicosis) autoimmune reactions (rheumatoid arthritis, glomerulonephritis, multiple sclerosis)
Chronic inflammation
chronic inflammatory cells ("round cell" infiltrate)
lymphocytes plasma cells monocytes/macrophages activation of macrophages by various mediators - fight against invaders
lymphocytes plasma cells, cytotoxic (NK) cells, coordination with other parts of immune system plasma cells - production of Ig monocytes-macrophages-specialized cells (siderophages, gitter cells, mucophages)
3. proliferative
primary (rare) x secondary (cholecystitis)
2c. suppurative (purulent) - accumulation of neutrophillic leucocytes - formation of pus (pyogenic bacteria) interstitial
phlegmone diffuse soft tissue abscess - localized collection
acute border surrounding tissue chronic border - pyogenic membrane Pseudoabscess pus in lumen of hollow organ
formation of suppurative fistule accumulation of pus in preformed cavities - empyema (gallbladder, thoracic)
complications of suppurative inflamm.: bacteremia (no clinical symptoms!; danger of formation of secondary foci of inflamm. (endocarditis, meningitis) sepsis (= massive bacteremia) - septic fever, activation of spleen, septic shock thrombophlebitis - secondary inflammation of wall of the vein with subsequent thrombosis - embolization pyemia - hematogenous abscesses (infected infarctions) lymphangiitis, lymphadenitis
2d. pseudomembranous - fibrinous pseudomembrane (diphtheria - Corynebacterium, dysentery - Shigella) - fibrin, necrotic mucosa, etiologic agens, leucocytes 2e. necrotizing - inflammatory necrosis of the surface - ulcer (skin, gastric)
gangrenous - secondary modification by bacteria - wet gangrene - apendicitis, cholecystitis - risk of perforation - peritonitis
Granulomatous inflammation
distinctive chronic inflammation type cell mediated immune reaction (delayed) aggregates of activated macrophages epithelioid cell multinucleated giant cells (of Langhans type x of foreign body type) NO agent elimination but walling off intracellulary agents (TBC)
Granulomatous inflammation
1. Bacteria
TBC leprosy syphilis (3rd stage)
4. Foreign body
suture (Schloffer tumor), breast prosthesis
5. Unknown - sarcoidosis