The diagnosis is made by considering your dog's clinical signs and breed. Your vet will rule out other possible causes for your dog's skin lesions, such as bacterial or fungal infections and autoimmune disorders. A definitive diagnosis is made by taking a sample of your dog's skin lesions. A lab can look at the sample under a microscope to see if they have a zinc deficiency. If a zinc deficiency is to blame, a lab will tell your vet that their skin shows parakeratotic hyperkeratosis with inflammation. Your vet will also ask you questions about your pet's diet to see if it contains enough zinc. If it does, a type I zinc-responsive dermatosis diagnosis may be given to your dog.