Cutaneous mastocytosis

Question 1

What is the frequence and pathomechanism of feline cutaneous mastocytosis

Answer 1

Feline cutaneous mastocytosis is a rare skin disorder characterised by a pathological infiltrate of inceeased numbers of mast cells in the skin

Question 2

Describe the two forms classically described in humans

Answer 2

The systemic form:
- associated with mast cells infiltrate in the bone marrow and/or other organs, with frequent cutaneous involvement (it is thus important to always consider the possibility of underlying systemic mastocytosis in cats presenting with cutaneous mastocytosis)
- mostly observed in adults
- potentially poor prognosis

Question 3

What are the three clinical presentations for cutaneous mastocytosis

Answer 3

A dermatitis with large papular lesions, as well as wheals, mainly localised to the head, shoulders, ventral neck and axillae associated with moderate pruritus

A small maculopapular erythematous dermatitis often associated with crusts and moderate pruritus

A highly pruritic, more chronic dermatitis with erythema, coalescing papules, wheals, hyperpigmentation, lichenification

Question 4

What are the main differentials for feline cutaneous mastocytosis

Answer 4

Dermatophytosis

Mast cell tumor
- typically not pruritic
- found in older cats

Question 5

What is the median age of presentation

Answer 5

15 months (< 5 years)

Question 6

Are there any breed overrepresented

Answer 6

Sphinx

Devon Rex

It is interesting that this disease has been recognized mainly in hypotrichotic or naked animals