Allergy to What? Flashcards
What are the three main causes of allergic skin disease?
- Flea allergy dermatitis
- Adverse food reactions
- Atopic dermatitis
How can you test for FAD?
Test for flea allergen
- Serology
- Intradermal
BUT all positives are indicative that they have been exposed so lots of false negatives
What are the signs of adverse food reactions indistinguishable to?
Atopic dermatitis
What clinical signs are suggestive of food allergy?
Concurrent GI signs in 30-60% of AFR dogs - increased defecation, flatulence, perianal pruritus
Age of onset <1year/6m
>50% GC resistant
If you suspect an AFR what should you suggest as management?
Trial food - elimination diet in all cases
>6-10 weeks exclusive diet
Followed by dietary re-challenge
If no relapse after 14d then no food allergy
Which food to pick for an elimination food trial?
Commercial limited protein source = Hills d/d
Hydrolysate = Purina HA, Hills z/d, RCW, anallergenic - proteins are chopped down so immune system can’t recognise
Home cooked novel protein - rabbit, horse, white fish
Should you use medication during a food trial?
Ectoparasite control
AB are allowed
Antiinflammatories only for first 3 weeks then taper
When should you definitely attempt to do a food trial?
In YOUNG dogs, there is good prognosis to manage without medication
What is the most common - food or environmental allergen?
Good = 20-30% Environmental = 70-80%
What should you do if an allergy is not food related?
Immunomodulation
ASIT
What is the efficacy of ASIT in dogs and horses?
Dogs - 60%
Horses - 80%
What tests can be used to identify environmental allergens?
Intradermal test
Serology
How does intradermal testing work?
Mast cell bound IgE- testint the ability of the mast cells to degranulate
Positive control - histamine
Negative control - saline
What are the drug withdrawal times before an intradermal test?
Antihistamines - 7d
GCs - 14d
Ciclosporin - 0d
