Rotties are among the breeds in which a hereditary vitiligo been described. White patches develop on the skin (leukoderma) and hair (leukotrichia) particularly on the nose, lips, mouth mucosa and face. Other areas can be affected including foot pads and nails. Onset is generally in young adult dogs (2-5).
The exact mechanism is unknown. Theories include immune mediated causes (antimelanocyte antibody formation), autotoxicity ( increased melanocyte susceptibility to destruction), nerve injury that affects melanocytes and viral association. Multiple mechanisms can be involved.
I can not associate stiffness with vitiligo; however, nail disease could cause pain and lameness.
Vitiligo is seen in other species including humans, cats and horses.
No successful treatment has been identified although rare cases regress spontaneously. The upside is that it is largely cosmetic. The exception is that affected nails may be shed and secondary infection can occur.
There are acquired causes of hypopigmentation, which may appear as graying or white spots. Inflammation can cause decreased pigmentation. Bite wounds often are marked by white hair. It can also develop secondary to a contact dermatitis from plastic an drubber food dishes, some drugs and some skin cancers. The skin and hair changes are cosmetic, but the underlying condition in acquired cases is not always benign.
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