A precise diagnosis of the causes of a skin disease requires a detailed history, physical examination, and appropriate diagnostic tests. Many skin diseases have similar signs and an immediate diagnosis may not be possible. Based on your dog’s history and the physical examination, your veterinarian may order any of a number of laboratory procedures. These may include microscopic analysis of skin scrapings and hair, cultures of hair or skin swabs, specialized skin tests, blood and urine tests, and even biopsies. It may take several days before laboratory results are available. Your veterinarian may also evaluate how your dog responds to treatment in order to diagnose a specific skin problem. More than one visit is often required for an accurate diagnosis.
Also see professional content regarding diagnosis of skin diseases.