Urticaria Pigmentosa-Like Skin Disease in a Domestic Shorthair Cat

A 14-month-old castrated male domestic shorthair cat with severe pruritus, alopecia, papules, and excoriations was diagnosed with urticaria pigmentosa (UP) after an extensive diagnostic work-up. Skin biopsy revealed numerous well-differentiated monomorphic mast cells in the superficial dermis. The cat showed significant improvement and hair regrowth with oral dexamethasone and cetirizine hydrochloride treatment. This case underscored the importance of biopsy for diagnosing uncommon diseases like UP and demonstrated the effectiveness of combined steroid and antihistamine therapy. It was the first reported case of UP in a domestic shorthair cat.