DR: Feline allergic skin disease

Question 1

List the important clinical presentation of feline allergic skin disease

Answer 1

• miliary dermatitis
• indolent (lip) ulcer
• eosinophilic plaques
• linear granuloma

Question 2

Describe the lesion - miliary dermatitis

Answer 2

• Focal areas of crusting (often haemorrhagic)
• some papules,
• alopecia in advanced cases.
• May be easier to feel than to see at the beginning.
• Typically on dorsum/caudal dorsum

Question 3

Typical lesion - indolent (lip) ulcer.

What is the ddx for this?

Answer 3

• well circumscribed ulceration on upper lip,
• most commonly on either side of the philtrum or the hard palate.
• 5mm to 5cm in length
• (Ddx = SCC!)

Question 4

Typical lesion - eosinophilic plaques

Answer 4

• alopecic raised erythematous, erosive or ulcerated lesion.
• Typically trunk, inguinal area or caudal thighs.
• Can become large (several cm in diameter),
• pruritic

Question 5

Typical lesion - linear granuloma

Answer 5

Similar to plaque in appearance but linear.
The plaque typical lesion is as follows:
- alopecic raised erythematous, erosive or ulcerated lesion.
- Typically trunk, inguinal area or caudal thighs.
- Can become large (several cm in diameter),
- pruritic

Question 6

What are the most important ddx for feline allergic skin disease?

Answer 6

• Allergies (fleas, food, environmental, insects),
• ectoparasites (Cheyletiella, fleas, ear mites, harvest mites),
• FBs
• irritant substances,
• dermatophytosis,
• neoplasia

Question 7

How do you confirm feline allergic skin disease?

Answer 7

• Hx and CS (previous allergy, young animal, previous response to GCs, flea control, otherwise healthy)
• rule out parasites (coat brush, skin scrape, hair pluck)
• rule out ringworm and bacterial infection (cytology and bacterial/ fungal culture)
• if all of above are ruled out –> clinical diagnosis of allergic disease. Then perform food trial and allergy testing.

Question 8

Define the term “Eosinophilic granuloma complex

Answer 8

Clinical entities (mainly eosinophilic plaque, eosinophilic granuloma, indolent ulcer) grouped together. This complex refers to a reaction pattern of (mostly feline) skin. It is NOT a diagnosis and can be caused by various different triggers. MOSTLY EOSINOPHILS AND MAST CELLS ARE INVOLVED.

Question 9

Typical lesion for mosquite-bite hypersensitivity 2

Answer 9

• alopecia on bridge of nose

- alopecia +/- crusting on pinnal edges