Vitiligo

VITILIGO CAN BE DEFINED AS A RARE AUTOIMMUNE DISEASE thought to selectively destroy epidermal melanocytes, leading to loss of pigment in the affected area (Paterson, 2008). Clinically this leads to patchy areas of depigmented skin (leukoderma) or hair (leukotrichia). The disease is uncommon in the dog and rare in the cat.

Pathogenesis

Antimelanocyte antibodies were demonstrated in 17 Belgian Tervuren dogs with Vitiligo and in none of 11 normal dogs of that breed. Similarly, three affected Siamese cats with Vitiligo had antimelanocyte antibodies while four normal Siamese cats did not (Naughton and others, 1986). There has beenv little information on the pathogenesis in companion animals since this article was published. A case of generalised Vitiligo has been described in a dog with primary hypoadrenocorticism (Malerba and others, 2015). The authors concluded that dogs with immunemediated disease might develop other manifestations of this group of disorders including a combination of Addison’s disease/Vitiligo. There is also a recent case report of depigmentation associated with the administration of toceranib in a Bernese mountain dog (Cavalcanti and others, 2017).

Clinical features

• There is no sex predilection.
• More commonly seen in young dogs.
• Lesions occur mainly on the nose
• Any breed may be affected, but there are some predisposed breeds. These include the Belgian Tervuren, German shepherd, Collie, Rottweiler, Doberman pinscher and Giant Schnauzer (Hnilica and Patterson, 2017).
• Lesions in the cat are similar but rarer, with Siamese cats predisposed.