A 5 year-old mixed breed dog is seen in your practice as an emergency because of severe bleeding of the margins of both ears which the owners tried to stop with tapes (picture 1). Similar problems have occurred several times over the last couple weeks but never so bad as this time. 3 days before the dog had also shown epistaxis.
The owners exclude an intoxication with dicumarol derivates because they live in the center of a big city and the dog is always on the leash when they go for walks.
When you do your clinical examination, you note a severe exfoliative dermatitis on the complete head and a mild depigmentation of the planum nasale (picture 2). All footpads are hyperkeratotic and the growth rate of the claws is markedly accelerated (picture 3).
Which differential diagnosis could explain all these signs?