Pruritis in Cats

Question 1

What must always be ruled out in suspected Feline Atopic Skin Syndrome?

Answer 1

Feline Atopic Skin Syndrome: associated w/ environmental allergies - young cats (0.5-4.8 years), female (58.4%)

R/O = food, FLEA BITE HYPERSENSITIVITY!!, ectoparasite, hypersensitivty disorders

Question 2

What are the 4 reaction patterns of FASS?

Answer 2

1. Miliary dermatitis
2. Self-induced alopcia / hypotrichosis
3. Head & neck pruritis
4. Eosiniphilic granuloma complex

Question 3

Which FASS reaction pattern?

Answer 3

Miliary Dermatitis
- 1-2 mm papules
- Pruritic!! -> excoriations, erosions, alopecia

Papule: small, solid elevation (≤ 1cm in diameter) filled with inflammatory cells/edema -> a coalition of papules = plaque

Question 4

What is the most likely cause for Self-Induced Alopecia / Hypotrichosis

Alopecia is the absence of hair; hypotrichosis, which is much more common, is the presence of less hair than normal.

Answer 4

Pruritis –> overgrooming

Psycogenic alopecia (OCD) also possible cause

Question 5

Which reaction pattern of FASS is this?

Answer 5

Eosinophilic Granuloma Complex –> Indolent Ulcer (rodent ulcer)

• Non-pruritic unless a 2º bacterial infection is present

can result in entire deformation of rostral portion lip

Question 6

Which reaction pattern of FASS is this?

Answer 6

Eosinophilic Granuloma Complex –> Eosiniphilic Granuloma (or “linear granuloma”)

• mouth (tongue, hard palate)
• rear legs
• may see chin-swelling

Question 7

Which reaction pattern of FASS is this?

Answer 7

Eosinophilic Granuloma Complex –> Eosinophilic Plaque

• ventral abdomen; medial thighs
• pruritis -> overgrooming -> saliva-staining

risk = 2º bacterial infections

Question 8

How is Eosiinophilic Granuloma Complex-caused FASS diagnosed?

Answer 8

Biopsy!
- r/os = neoplasia (SCC, MCT, lymphoma), infectious granulomas, abscess

Question 9

How to rule out flea allergy dermatitis?

Answer 9

Strict flea control

Question 10

How to rule out food allergy dermatitis?

Answer 10

strict food trial (6-8 weeks!)

Question 11

How to rule out 2º bacterial & yeast infections?

Answer 11

bacterial infections be present in up to 48.9% of allergic cats
-> otic and skin cytology MANDATORY

Question 12

What is the risk of treating FASS cases with Cyclosporine (Atopica)?

Answer 12

Toxoplasmosis!

Cyclosporine has multiple mechanisms of action, ranging from inhibiting T-cell activation; histamine release; cytokine production; and eosinophil migration, survival, and degranulation.

Because fatal systemic toxoplasmosis has been reported, avoid cyclosporine use in cats with high risk for toxoplasmosis (eg, cats that hunt). Contraindications for use include demodicosis, neoplasia, dermatophytosis, and systemic fungal infection.

Question 13

Which drug is sometimes used off-label in FASS cases?

Answer 13

Oclacitinib (Apoquel) – only is on-label in dogs. start tx with cyclosporine, unless contrainidicated / toxo risk is high

Question 14

Side effects of glucocorticoid tx for FSSA?

Answer 14

Cats have fewer steroid receptors than dogs -> HIGHER doses required! But, are MORE RESISTANT to side effects verss dogs.

Prednisolone