Allergy Flashcards Preview

Hugh's MD2 Core Conditions and Presentations > Allergy > Flashcards

Flashcards in Allergy Deck (28):
1

Which diagnostic test can be used post anaphylaxis to confirm it?

Mast cell tryptase

2

How are seasonal allergic rhinitis treated?

Nasal corticosteroids

Anti-histamines

3

How is insect allergy treated?

5 years of immunotherapy

4

How are symptoms related to location of exposure in non-anaphylaxis allergy?

Symptoms typically appear at the site of exposure

5

What are the mechanisms of the chronic allergic reaction?

Eosinophils release of basic proteins, leukotrienes

Continued release of mast cell histamine, lipids

Neuropeptides released from Th2 cells

6

How is adrenaline best administered in anaphylaxis?

0.5mg IM

Wait 5 minutes and give more if needed

After 3 administration considerd infusion

7

What is the gold standard of allergen testing?

Challenge testing

8

What is a non-sedative anti-histamine?

Cetirizine

9

When are challenge tests used?

Usually used when RAST and SPT negative/discordant and there is a good clinic story

10

What are the diagnostic tests for IgE allergy?

Skin prick test

Serology - CAP

Challenge test

11

Who should get subcutaneous injection immunotherapy?

Venom allergy

Allergic rhinitis

Mild, well controlled allergic asthma

12

Why do thunderstorms exascerbate allergies?

Storm break up pollen seeds allowing them to travel deeper into the lung

13

What is the dose of adrenaline for anaphylaxis in adults and children?

0.5mg in adults

0.01mg/kg

14

How does subcutaneous injection immunotherapy work?

Injecting allergen subcutaneously at increasing doses over longer time periods

Class switching the response to an allergen to IgG

15

What are the advantages and disadvantages of in vitro assays?

Adv
Highly available

Safe

Specific

Standardised and quantitative

 

Neg

- High false positive rate

- Medicare only subsizes 4 allergen at once

16

What is the new alternative to subcutaneous injection immunotherapy? What are the advantages?

Sublingual immunotherapy

 

Easier to administer

Less anaphylaxis risk

17

How can you treat allergies?

Subcutaneous allergen immunotherapy

18

What is the criteria for a positive skin prick test?

>3mm

19

Which age group is most likely to die from anaphylaxis?

16-24

20

What is the cardiovascular response in anaphylaxis?

Hypotension

21

What is the mechanism of anaphylaxis?

Massive mediator release from mast cell and basophils 

Histamine causes vasodilation, fluid extravasation, bronchial smooth muscle contraction and mucosal oedema 

22

What is the definition of anaphylaxis?

Generalised  IgE-mediated response involving the cardiovascular and/or respiratory system

23

How can you treat anaphylaxis?

Avoiding trigger

Management of inadvertent exposure

24

What are some milder symptoms of anaphylaxis?

Pruritis

Vomiting, diarrhoea

Flashing, urticaria

25

What are the major sources of fatal anaphylaxis?

Medications 50%

Insects 25%

Food 20%

26

Define what an allergy is

An inappropriate or harmful immune response to foreign substances that are otherwise not harmful to the body, mediated largely, though not exclusively by immunoglobulin E (IgE)

27

What are the advantages and disadvantages of the skin prick test?

Adv - Highly sensative (99%)

- In vivo

- Fast results

 

Disadv - May lack sensitivity due to sensitized but asymptomatic patients

- Potential for anaphylaxis

 

28

How do you measure allergen specific IgE?

RAST (radio-allergosorbent test)

EAST