Anaphylaxis

Question 1

What cells cause symptoms?

Answer 1

Mast cells and basophils

Question 2

Which signalling molecules are involved?

Answer 2

IL-4, IL-13, IgE, histamin, leukotriene

Question 3

What antibody class is involved?

Answer 3

IgE

Cross-linking by antigen triggers mast cell activation and histamine release

Question 4

What are symptoms of anaphylaxis?

Answer 4

Skin allergies can cause:
Oedema, redness, itching, rashes,

Food allergy can cause:
vomiting, nausea, rashes

asthma and hay fever can cause :
-breathlessness, coughing and itching

Question 5

What causes rashes and puffy skin?

Answer 5

In connective tissue, histamine causes dilation of vessels with increased blood flow to surface and oedema

Question 6

Why should adrenaline be given to someone having anaphylactic shock?

Answer 6

Adrenaline (epinephrine) constricts peripheral blood vessels and redirects blood to organs

Question 7

What drugs may be given?

Answer 7

Anti- histamines
Corticosteroids
Oxygen and bronchodilators

Question 8

What causes patients to feel faint?

Answer 8

Hypotension: low Bp
Syncope: temporary loss of consciousness due to drop in blood flow to brain

Question 9

How in anaphylaxis controlled long term?

Answer 9

Avoid known allergens
May be given adrenaline in self injection e.g. EpiPen
Skin patch test