food allergy and resp allergy

Question 1

Can you develop an allergy against lactose?

Answer 1

No! Only against proteins! Lactose is a sugar!

Question 2

Which allergies persist to adulthood vs go?

Answer 2

Milk and effs - go

peanuts, wheat, nuts, shellfish, fish persist to adulthood

Question 3

Should an atopic mother avoid peanuts in preg?

Answer 3

No

Early age exposure from 4 months and older ok

Question 4

Gold standard for IgE mediated food allergy?

Answer 4

Food challenge

Question 5

When is tryptase high?

Answer 5

1-4 hours post anaphylaxis but VERY UNCOMMON with food anaphylaxis

Question 6

React to peanuts, likely to react to…

Answer 6

lentils, peas, legumes
10% also soy allergy
treenuts
sesame often

note NOT cross reacting but tend to group allergies.

Question 7

If someone has exercise induced anaphylaxis, what should you check?

Answer 7

Find out the underlying food acting as cofactor and avoid 4-6 hours pre exercise
test recombinant omega-5-gliadin IgE

Question 8

Factors that increase risk death in anaphylaxis?

Answer 8

asthma
delayed adrenaline
eating away from home and allergic  food
40-50s and insect or drug allergy
teenagers and food allergy

Question 9

How does Omalizumab work?

Answer 9

binds Fc portion of IgE , prevents from binding to mast cells and back on to dendritic cells
Can use in asthma where there is INCREASED TOTAL IgE, sensitised to perennial aerosols, frequent exac, high dose inhaled steroids.

Question 10

management of allergic rhinitis

Answer 10

avoidance
antihistamines and IN steroids
desensitisation subling or subcut

Question 11

Egg allergy strong assoc with….

Answer 11

atopic dermatitis

Question 12

Skin prick for food allergy testing?

Answer 12

Yes but NEVER intraderma- much higher risk of severe reaction

Question 13

Insect sting allergy- do you do intradermal testing?

Answer 13

Yes, both skin prick and intraderma testing done here

Note POOR CORRELATION with insects between size of positive skin test, IgE level and severity of allergy

Cannot desesnitise someone to an insect thing if just a large local reaction. Cutaneous systemic reaction and anaphylaxis can have immunotherapy

Cannot re-check IgE or skin prick post desens- not useful

Question 14

Does tryptase help tell between IgE mediated and non IgE mediated causes of mast cell degranulation?

Answer 14

No

Question 15

Can you do desens to med for type 2-4? SJS/TEN? haemolytic anaemia? interstitial nephritis?

Answer 15

No

Question 16

Does pen/ceph cross reactivity relate to generation of cephalosporin?

Answer 16

Earlier- more cross reactivity

Later- less so

Question 17

Sulphonamide reaction in HIV vs non HIV?

Answer 17

more common ++ in HIV positive

often delayed 7-10 days; fever, pruruitis

Question 18

Most common NMDA to cause anaphylaxis?

Answer 18

succinylcholine

good sens on skin prick testing

Question 19

latex what type of hypersens?

Answer 19

Type 1 and 4

can do SPT or specific IgE or challenge

Question 20

Does seafood allergy increase risk of contrast allergy?

Answer 20

No - it is a contrast allergy to the protein of the seafood not the iodine

Can do SPT for immediate type - but low sens
Cannot do IgE
Can do patch testing for delayed type

Question 21

How to investigate chlorhex reaction?

Answer 21

IgE sens and specific

SPT sens and spec good

Question 22

Mechanism for ACE angioedema

Answer 22

Bradykinin usually broken down by ACE into inactive metabolites. Instead shunted in to BK2R–>NO and increase vasc permeability

NO correlation with cough

NOT IgE mediated

Question 23

NSAID allergy is mediated by?

Answer 23

When block COX 1 and 2, the arachidonic acid is shunted from the prostaglandin pathway to the lipoxygenase pathway–>lots of leukotrienes

Clopidogrel no cross reactivity if properly aspirin allergic
Diagnose by challenging with COX1 and if pos then COX2
Desensitisation only good for NON anaphylaxis

Question 24

Is there immunotherapy for food allergy?

Answer 24

No