HYPERSENSITIVITIES Flashcards
1
Q
What is type I hypersensitivity reaction?
A
anaphylactic
2
Q
mechanism of type I
A
IgE binds to mast cells
3
Q
examples of Type I
A
anaphylaxis
atopy
4
Q
type II - what is it?
A
cell bound
5
Q
mechanism of type II
A
IgG or IGM binds to antigen on cell surface
6
Q
examples of Type II
A
- Autoimmune haemolytic anaemia
- ITP
- Goodpasture’s syndrome
- Pernicious anaemia
- Acute haemolytic transfusion reactions
- Rheumatic fever
- Pemphigus vulgaris / bullous pemphigoid
7
Q
type III - what is
A
immune complex
8
Q
mechanism of type III
A
free antigen and antibody (IgG, IgA) combine
9
Q
examples of type III
A
- Serum sickness
- Systemic lupus erythematosus
- Post-streptococcal glomerulonephritis
- Extrinsic allergic alveolitis (especially acute phase)
10
Q
type IV - what is it
A
Delayed hypersensitivity
11
Q
mechanism of type IV
A
t-cel mediated
12
Q
examples of type IV
A
- Tuberculosis / tuberculin skin reaction
- Graft versus host disease
- Allergic contact dermatitis
- Scabies
- Extrinsic allergic alveolitis (especially chronic phase)
- Multiple sclerosis
- Guillain-Barre syndrome
13
Q
type V mechanism
A
antibodies that recognise and bind to the cell surface receptors.
This either stimulating them or blocking ligand binding
14
Q
examples
A
Graves’ disease
Myasthenia gravis