Click here to load reader
Upload
shiroeki
View
256
Download
1
Tags:
Embed Size (px)
DESCRIPTION
Pathology - Inflammation
Citation preview
DR SHWE SIN
M.Med.Sc
FMHS
OVERVIEW OF INFLAMMATION INFLAMMATION : is a protective response involving host cells, blood vessels, and proteins and other mediators that is intended to eliminate the initial cause of cell injury as well as the necrotic cells and tissues resulting from the original insult and to initiate the process of repair.
PURPOSE OF INFLAMMATION To bring phagocytic cells to the injured area
to engulf invading bacteria
To bring in factors from the serum to neutralize the infectious agents
To serve to destroy, dilute, wall of the injurious agent and tissue cells that it may have destroyed
Although inflammation clear infections, noxious stimuli & initiate repair cause harm (capable of injuring normal tissue)
Inflammation is induced by chemical mediators in response to injurious stimuli that are produced by host cells
The main components are vascular reaction and cellular response
CLASSIFICATION OF INFLAMMATION I. Based on duration: i) Acute inflammation ii) Chronic inflammation II. Based on characteristic of exudates: i) Serous inflammation ii) Fibrinous inflammation iii) Suppurative or Purulent inflammation iv) Haemorrhagic inflammation v) Mixed III. Based on location: i) Abscess ii) Ulcer iii) Membranous inflammation iv) Catarrhal inflammation v) Cellulitis
Features of Acute and Chronic Inflammation***
Feature Acute Chronic
Onset Fast: minutes or hour Slow: days
Cellular infiltrate Mainly neutrophils Monocytes/ macrophages & lymphocytes
Tissue injury, Fibrosis Usually mild and self-limited
Often severe and progressive
Local & Systemic signs Prominent Less prominent; may be subtle
Local Cardinal Signs of Inflammation
Heat (calor)
Redness (rubor)
Swelling (tumor)
Pain (dolor)
Loss of function (functio laesa)
CHEMICAL MEDIATORS
May be produced by cells or may be circulating in the plasma.
Cell-derived mediators are sequestered in intracellular granules (histamine, prostaglandins and cytokines)
Plasma-protein-derived mediators (complement proteins and kinins)
Cell-Derived Mediators 1. Vasoactive amines
2. AA metabolites
3. Platelet activating factors
4. Cytokines
5. Chemokines
6. Reactive oxygen species
7. Nitric oxide
8. Lysosomal Enzymes of Leukocytes
9. Neuropeptides
Plasma Protein-Derived Mediators
1. Complements
2. Coagulation and Kinin System
General Principles of Chemical Mediators * Mediators originate either from plasma
or cells
* Most mediators perform their biologic
activity by initially to binding to
specific receptors on target cells
* A chemical mediator can stimulate the
release of mediators by target cells
themselves
* Mediators can act on one or few target
cell types
* Once activated and released from the
cell, most of these mediators are short-
lived
* Most mediators have the potential to
cause harmful effects
Systemic Effects of
Inflammation I. Acute Phase Response
i) Fever (Prostaglandin PG)
ii) Elevated levels of acute-phase
proteins (C-reactive protein CRP,
fibrinogen and serum amyloid A (SAA)
iii) Leucocytosis (rise in number of
immature neutrophils in the blood (shift
to left)
II. In Chronic Inflammation:
i) Disseminated intravascular
coagulation (DIC)
ii) Hypoglycemia
iii) Hypotensive shock
REFERENCE Robbins Basic Pathology, 8th Edition
Robbins Basic Pathology, 9th Edition