Allergy Flashcards
Adrenaline dose for anaphylaxis
IM doses of 1:1000 adrenaline (repeat after 5 min if no better)
* Adult 500 micrograms IM (0.5 mL)
* Child more than 12 years: 500 micrograms IM (0.5 mL)
* Child 6 -12 years: 300 micrograms IM (0.3 mL)
* Child less than 6 years: 150 micrograms IM (0.15 mL)
What is a type 1 allergy?
Type 1 hypersensitivity: anaphylaxis, IgE
What is a type 2 allergy?
Antibody mediated IgG or IgM, eg blood transfusion reaction, pemphigus vulgaris
What is type 3 allergy?
Immune complex mediated, rheumatoid or post strep glomerulonephritis
What is type 4 allergy?
Antibodies act on hormone receptors, eg Grave’s
What are the most common atopic conditions?
Eczema, food allergy, allergic rhinitis (hayfever), asthma
Cause of eczema
Fillagrin gene, stratum corneum dysfunction barrier, water loss
Food allergy Qs
Food, onset, symptoms, reproducibility, exclusion/reintroduction
Feeding hx, breast/bottle/weaning
Food allergy Ix
Weight/height (failure to thrive)
If IgE mediated- blood test
House dust mite avoidance
Avoid carpet
Coverings of pillows/duvets/matress
Washing sheets, blankets weekly at 60º
Steam cleaning carpet
Will they grow out of their allergy?
Yes, esp egg/wheat
Nut/shellfish less likely
Asthma key features
Cough, wheeze, SOB/exercise intolerance
Early morning symptoms
Triggers (cold air/pets/exercise/viral infection)
occupational trigger
Diagnosis asthma
FeNO if age 17 or over
Spirometry with reversibility
Peak flow diary 2-4 weeks
Trial ICS
Treatment allergic rhinitis
PO or intranasal antihistamine
Intranasal sodium cromoglycate
Intranasal steroid during allergen exposure
Intranasal ipratropium
Short term intransal xylometazoline decongestant
Montelukast trial if +asthma
If severe, course PO steroid/allergen immunotherapy
When do you refer to 2ndary care for food allergies?
Systemic symptoms
Food allergy + uncontrolled asthma
Reaction to trace allergen (skin/air)
When should you prescribe adrenaline auto-injector?
Anaphylaxis whilst waiting allergy clinic appt
If angiodema + asthma/COPD/heart disease
Angiodema with trace amounts allergen
If cannot avoid allergen (eg bee stings)
Treatment of mod/severe eczema baby under 6m old?
Trial hydrolysed/AA milk
Breastfeeding then trial food exclusion with dietetic support
Steroid potency +antimicrobial option
Mild
Hydrocortisone
Mild with antimicrobials
Canesten HC
Daktacort
Fucidin H
Moderate
Betnovate-RD
Eumovate
Moderate with antimicrobials
Trimovate
Potent
Betnovate
Elocon
Potent with antimicrobials
Fucibet
Very potent
Dermovate
How do you diagnose CMPI?
If breastfeeding, improvement without dairy + symptoms with reintroduction 2-4 weeks after elimination
Management CMPI
Once confirmed, cow milk free diet for at least 6m, until age 9-12m
Milk ladder if no active dermatitis or IgE/skin prick negative and no immediate symptoms
If immediate symptoms/positive test then may need supervised challenge
Soy not under 6m, other milks poor nutritional value
Signs non IgE mediated CMPI
Constipation, perianal redness, loose stools, colic
