10 - infectious & allergic disorders (pruritic!)

Question 1

(malassezia dermatitis)

1. what is this?
2. pruritic?

Answer 1

1. secondary (always) yeast infection
2. INTENESLY

Question 2

(malassezia dermatitis)

1. skin looks how?
2. distribution on body?

Answer 2

1. lichenified and hyperpigmented
2. axilla, groin, ventral neck, and abdomen (any moist warm area)

Question 3

(malassezia dermatitis)

1. dx?
2. tx = topical/oral antifungals

Answer 3

1. organisms on cyto, Cx

Question 4

(Atopy - Atopic Dermatitis)

1. what is it?

Answer 4

1. type 1 hypersensitivity to environmental allergens -> IgE

Question 5

(atopic dermatitis)

1. Cx signs usually noted at what age?
2. what does the IgE do?

Answer 5

1. 1-3 years

(development of Cx requires second exposure following the initial exposure (sensitization))

2. degranulation of mast cells

Question 6

(atopic dermatitis - Cx)

1. seasonal to non-seasonal pruritis
2. most affected regions?
3. most lesions from what?
4. very commonly get secondary what?

Answer 6

2. face and feet, also get chronic otitis externa
3. secondary to self-trauma
4. bacterial and yeast infections

Question 7

(atopic dermatitis - dx)

1. what is the hallmark of this dz?
2. allergy testing useful for what?

Answer 7

1. pruritis

(this is a dx of exclusion)

2. determining what animal is allergic to, NOT to dx atopy

Question 8

(atopic dermatitis - tx)

1. avoidance if possible
2. do corticosteroids work?
3. topical antipruritic and bathing therapy will help decrease antigen exposure
4. cyclosporine

Answer 8

2. yes

(antihistamines can be used as well to allow for lower dose)

Question 9

(food allergy)

1. typically occurs do to what in diet?

Answer 9

1. protein source

(changing protein source usually works)

Question 10

(food allergy - Cx)

1. nonseasonal pruritis
2. lesions 2° to self trauma
3. secondary yeast and bacterial infections common
4. typically what age?

Answer 10

4. can occur in animals of any age!

Question 11

(dx)

1. how to dx?

Answer 11

1. elimination diet trial -> decrease in pruritis of 50% of more -> confirmed by ^pruritis w/ food challenge

Question 12

(food allergy - tx)

1. avoidance
2. corticosteroids?
3. topical antipruritic therapy

Answer 12

2. can work but not as well as for atopic dermatitis

(can also consider antihistamines)

Question 13

(contact dermatitis)

1. rare cause of skin dz
2. typically occurs where?
3. what type of hypersensitivity?

Answer 13

2. thinly haired body regions (hair provides protection)
3. type 4 (cell mediated)

Question 14

(irritant contact dermatitis)

1. inflammatory reaction to an irritating substance rather than immunologic like contact allergy

which is more common?

2. tends to affect what areas?

Answer 14

1. irritant much more common
2. thinly haired (less protection)