Inflammation Flashcards
(44 cards)
What is Exudate
- fluids rich in proteins and cells flow from vessels into interstitium/body cavities
- implies big changes in normal permeability of small blood vessels in that area
What is Transudate
- fluids with little protein (albumin) flows = “ultra filtrate of plasma”
- due to hydrostatic imbalance
- permeability is normal
What is Edema
- excess interstitial fluid
What is Pus
- purulent exudate
- cell rich with mainly PMNs and cell debris
- powerful lysosomal enzymes
5 Characteristics of Inflammation
- redness
- swelling
- heat
- pain
- impaired function
Oxygen-Dependent Bactericidal Mechanisms
- H2O2 myeloperoxidase halide system (most efficient)
- Cl- = physiological halide
- HOCl = final reactive radical
- powerful oxidant and antimicrobial (chlorination) - MPO independent killing
- OH- = the free radical
**mocoytes lose MPO when transforming into macrophages
Reasons for a burst in oxygen use during phagocytosis
- increase of glycogenolysis
- increased glucose oxydance (hexose-monophosphate shunt)
- production of active oxygen metabolites via 2 oxygen-dependent mechanisms
Oxygen-Independent Bactericidal Mechanisms
- increased lactate + action carbonic anhydrase –> increased H+ –> reduced intravacuolar pH
- action of substances from leukocyte granules
- degradation via acid hydrolase within phagolysosomes
During phagocytosis, leukocytes release..
- lysosomal enzymes
- oxygen derived metabolites
- products of arachidonic acid metabolism (prostaglandins, leukotrienes)
Leukocyte products are released during which three process during phagocytosis:
- regurgitation during feeding
- reverse endocytosis (frustrated phagocytosis)
- cytotoxic released (following cell death)
What are the mediators of increased vascular permeability?
- cell derived vasoactive mediators
- arachidonic acid metabolites
- platelet activating factors (PAFs)
- amines: histamine, serotonin
- endothelins
- plasma derived vasoactive mediators
- kinins and coagulation cascade
- complement system
What are the mediators involved in cell recruitment?
- C5a
- bacterial products
- arachidonic acid metabolites
- chemokine (IL-8) and other cytokines
Characteristics of Acute Inflammation
- dominant changes = vascular (vasodilation, inc permeab.) and exudative (fluids and cells)
- mainly PMN’s (because faster)
- short lived (due to treatment or self-limiting)
Characteristics of Chronic Inflammation
- when inflammation has lasted more than 2-4 weeks
- lots of proliferation of cells and connective tissue
- exudation is less conspicuous (lymphs, plasma cells)
- follows acute or chronic from onset, or chronic with persisting acute
- mainly mononuclear cells; macrophages, lymphocytes, plasma cells, eosinophils
Cells involved in acute
- PMNs
- other cells too though
Cells involved in chronic
- macrophages
- lymphocytes (NK, T, B cells)
- plasma cells (humeral immunity - mediated by Abs)
- eosinophils (for parasitic infections and allergic rxns)
Two types (and characteristics of) Chronic Inflammation
- non-specific
- no pattern of tissue ran
- cells = mononuclear cells (monocytes, lymphocytes, plasma cells) and connective tissue (fibroblasts) - granulomatous
- special tissue rxn
- cells = reticuloendothelial cells and their derivatives (macrophages)
- due to: certain infections (TB, syphillis), presistant foreign body infections, rheumatic fever, rheumatoid arthritis
Describe a granuloma
- central focus = nectrotic tissue (usually)
- surrounded by macrophages (modified to epithelioid cells)
- outer rim of lymphocytes and/or plasma cells
** giant cells (multinucleate because made up of macrophages combined together) are present among the inner cells
Serous Exudate
When? What? Examples? Identified how?
- mild injuries
- only albumin
- derived from secretions of serial mesothelial cells
Examples: burn blisters, pulmonary TB
Identified: difficult (abnormally dilated spaces, fine precipitate of protein)
Fibrinous Exudate (When? What? Examples? Identified how?)
- more severe
- contains fibrin (clot)
- in acute but also in active zones of chronic
- fibrin can be removed
Examples: rheumatic fever (bread and butter pericarditis), pneumococcal pneumonias
Identified: easily because precipitated fibrin is in strands and bands, in part fibrillar and is acidophilic (stained with acid stains)
Suppurative/Purulent Exudate
When? What? Examples? Identified how?
- liquefactive necrosis cause by pyrogens (pus-producing bacteria)
- exudate has lots of pus
Examples: characteristically in pyogenic infections by staphylococcus and pneumococcus etc., acute appendicitis, tooth abscess, zit
Identified: pools of numerous PMNs (viable and dead)
Sanguinous Exudate
When? What? Examples? Identified how?
- lots of RBCs
- indicates serious damage to endothelial
- almost never pure but in a mixed form with other type of exudate
Examples: TB, inflammations due to tumour invasion, frostbite, SARS
Identified: by RBCs in exudate
Abscess
- LOCALIZED collection of pus caused by suppuration
- caused by an irritant of great intensity (staph, turpentine) that stays localized leadings to lots PMNs coming
Paronychia
- infection around the fingernail
