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Flashcards in allergies Deck (13)
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1
Q

skin sensitisation theory

A
  1. break in infant skin allows allergen to enter bloodstream and react with immune system
  2. child does not have contact with allergen in GIT

if exposed to GIT, then recognised as food and not harmful

2
Q

hypersensitivity type 1

A

IgE antibodies trigger mast cells and basophils
histamines and cytokines released
immediate reaction

3
Q

hypersensitivity type 2

A

IgG and IgM activate complement system leading to direct damage to local cells

e.g. haemolytic disease of newborn

4
Q

hypersensitivity type 3

A

immune complexes accumulate and damage local tissues

e.g. SLE, HSP

5
Q

hypersensitivity type 4

A

cell mediated hypersensitivity by T cells

6
Q

gold standard test

A

food challenge testing

7
Q

Mx following exposure

A

antihistamines
steroids
IM adrenaline

close monitoring after allerigic reaction to ensure doesnt progress to anaphylaxis

8
Q

what is anaphylaxis caused by

A

T1 hypersensitivity reaction

9
Q

anaphylaxis: pathophys

A

IgE stimulates mast cells to rapidly release histamine and other pro-inflam chemicals

mast cell degranulation

10
Q

anaphylaxis: what differentiates it from non-anaphylxis allergic reactions

A

airway compromise

11
Q

anaphylaxis: Mx

A

IM adrenaline
antihistamines
steroids

observation after event as biphasic reactions can occur

12
Q

confirming anaphylaxis:

A

serum mast cell tryptase within 6hrs of event

13
Q

indications for epi-pen

A
  • Hx anaphylaxis
  • allergen cant be avoided
  • allergic to high risk allergen
  • idiopathic reaction
  • asthma