It needs to be differentiated from other causes of depigmentation of the nose including Canine Uveodermatologic Syndrome and immune-mediated disorders such as Discoid Lupus Erythematosus
The disorder shows as a light brown to pink discolouration of the otherwise black nasal planum. In some breeds (eg Bernese Mountain Dogs, Siberian Huskies and Golden and Labrador Retrievers it may be seasonal - being worse in the winter. In other breeds it is not seasonal. In some individuals the amount of pigment present may change from time to time, in others it remains depigmented.
Updated October 2013