Acute inflammation 1 Flashcards
what is inflammation?
first response of living tissue to injury
what are some causes of injury?
- Physical agents
- Chemicals
- Hypersensitivity
- Viral replication
- Microbial infection
- Necrosis
what are the physical characteristics of inflammation?
- Rubor (red)
- Tumor (swollen)
- Dolor (pain)
- Calor (heat)
- Loss of function
what is the suffix that indicates inflammation?
-itis
what causes appendicitis?
Waste fragment or infection
what are the symptoms of appendicitis?
Severe pain, loss of appetite, nausea
what is pericarditis?
Inflammation of the membrane surrounding the heart
what causes pericarditis?
Caused by infection, chest injury, radio/chemotherapy
what is meningitis?
Inflammation of protective membrane surrounding the brain and spinal cord
what are the symptoms of meningitis?
Fever, vomiting, headache, rash, stiff neck, aversion to light Within 8 hours: • Cold hands/feet • Leg pain • Unusually pale, mottled skin 13-22 hours: • Purple rash • Light sensitivity • Headache, Fever • Stiff neck • Drowsiness, coma
what happens if appendicitis is left untreated?
It can progress to peritonitis
What can meningitis lead to if left untreated?
Septicaemia, neurological problems, amputations and death
How is viral meningitis treated?
Painkillers, anti-sickness tablets
How is bacterial meningitis treated?
IV antibiotics
what happens during acute exudative inflammation?
escape of blood constituents into tissue, usually hours/days (can be longer)
what happens during chronic formative inflammation?
production of new fibrous tissue, prolonged tissue injury - weeks/months (can be shorter)
what are some problems with inflammation?
- severe allergy
- colitis/crohns disease
- rheumatoid arthritis
- Neurodegeneration
what is severe allergy?
Allergy/anaphylaxis involving 2 or more body symptoms
what can cause severe allergy?
Hypersensitivity (pollen, peanuts, dogs)
what are the symptoms of severe allergy?
Acute inflammatory swelling of the airway, mucosal membranes, hives
how can severe allergies be treated?
Antihistamines, corticosteroids, adrenalin (anaphylaxasis)
what is colitis?
Inflammatory bowel disorder
what can cause colitis/Crohn’s disease?
Genetic, immune reactions to gut bacteria, environment
what are the symptoms of colitis/Crohn’s?
Abdominal pain, diarrhoea, tiredness
how can colitis/Crohn’s be treated?
Anti-inflammatory drugs, steroids, immune-suppressants, surgery
what is rheumatoid arthritis?
Chronic progressive inflammation in joints leading to painful deformity and immobility in extremities
what causes rheumatoid arthritis?
Autoimmune – body’s own immune system attacks tissue leading to inflammation
what are the symptoms of rheumatoid arthritis?
Painful, swollen and stiff joints, fatigue
how can rheumatoid arthritis be treated?
Painkillers, steroids, anti-TNF therapy
what is neurodegeneration?
Neurodegeneration associated with Alzheimer’s Disease and Parkinson’s Disease (amongst others)
what are the symptoms of neurodegeneration?
AD – 7% > 65yo
Memory, cognition, behaviour
Plaques (APP), tangles (tau)
PD – 2% > 60yo
Movement, cognition, sleep
Lewy bodies (α-synuclein)
Changes in the activity of microglia
what are the pros of inflammation?
- Clears invading toxins
- Promotes healing
- Self-preservation
what are the cons of inflammation?
- Can become chronic
* Can lead to disease
what are the features of inflammation?
- fever
- lack of energy
- weakness
what is IL-1?
An endogenous pyrogen
where is IL-1 secreted from?
- Neutrophils
- Monocytes
- Macrophages
what is the function of IL-1?
- Acts on CNS thermoregulatory centre to increase temperature
- Acts on vascular system to increase dilation, more permeable
what are the phases of acute inflammation?
vasodilation
vascular permeability
emigration
chemotaxis
where does vasodilation occur?
mainly arterioles, venues and capillaries of microcirculation
what are the 3 stages in which blood flow changes?
constriction - reduced blood flow; tissue blanching
relaxation - increased blood flow; engorged capillary network
return to normal - blood flow slows back down; fluid loss and cell adhesion
what happens during vascular permeability?
Vessel wall becomes more permeable to fluids and proteins
what can vascular permeability lead to?
inflammatory oedema
what can inflammatory oedema lead to?
- Swelling
- Pain
- Relative immobility – loss of function
what is the exudate function of vascular permeability?
tissue repair
barrier
antibodies complement cascade
transportation
diluent
sustenance
what is the exudate like in mild inflammation?
watery (low protein) e.g. serous blisters
what is the exudate like in severe inflammation?
protein-rich e.g. lobar pneumonia
what happens in stage one of emigration of white blood cells?
- Drop out of main flow to the endothelial layer – margination
- Adherence to endothelium – pavem enting – cell adhesion proteins
What happens in stage 2 of the emigration of WBCs?
- Actively cross blood vessel wall – pseudopodia
* Flow through in amoeboid manner, pass basement membrane into tissues
what are example chemotactics for a neutrophil?
- leukotrienes e.g LTB4
- cytokines - IL-8
- complement system e.g. C5a
- collagen fibre fragments
- bacterial products e.g. LPS
- fibrinolytic system e.g. PAF
which white blood cell has faster migration, neutrophils or monocytes?
neutrophils
what are the functions of neutrophils in acute inflammation?
- bacterial phagocytosis
- lysosomal degradation
- cytokine production - attract further neutrophils/monocytes; IL-1 to increase temperature
when may eosinophils be involved instead of neutrophils?
- helminth
- hypersensitivity reactions e.g. hay fever
- enzymatic degradation of inflammatory mediators
what are the functions of macrophages in acute inflammation?
late arrival
phagocytosis - red blood cells, debris, bacteria
digest fibrin - inflammation resolution
What are chemical mediators of inflammation?
Substances which signal injury has occurred to blood vessels and cells
What are the properties of chemical mediators?
- Rapidly inactivated (enzymes)
- Direct, indirect or chemotactic
- Released/activated locally
- Widespread
- Linked interactions (amplification, +ve feedback, rapid response)
What are microglia?
Macrophages of the brain – they are the only immune cells in the brain
