Skin disease in dogs is a very common problem and it can have numerous causes. If your dog is suffering from a skin disease it can be confusing to you and uncomfortable for your pet. It may be helpful to try to distinguish between the different common skin diseases that dogs can have so that you and your vet can find the cause.
Dog Skin Disease and Allergies
The most common skin disease in dogs is allergies. Allergic dogs are itchy and scratch or chew themselves. They can be allergic to fleas, foods, or the environment. Fleas usually cause the dog to chew at the skin on top of the rump area, or around his belly. Food allergies can cause ear infections, facial itchiness, or intestinal upset. Environmental allergies, including dust, grasses, pollens, and molds, usually result in the dog chewing at his feet, rubbing his face or lips, or chewing at the area around his anus. Food allergies and environmental allergies have some overlap in signs but food allergies tend to be year round while environmental allergies can be seasonal. Click here to learn what treatment options are available for a dog with skin disease due to allergies!
Dog Skin Disease and Infectious Agents
Infectious agents are another cause of skin disease in dogs. Mite infections, including demodex mites and scabies mites, cause hair loss and varying degrees of itchiness. Demodex is a mite which is most commonly diagnosed in puppies and results in patchy hair loss on the head and neck area. Adult dogs can also get demodex but it’s not as common. Scabies is a contagious mite which causes severe itchiness and hair loss, usually most noticeable on the edges of the ears. Any age of dog can be affected by scabies. Click here to learn more about scabies and treatments. Ringworm is not a worm, but a fungus, which results in hair loss, redness, and flakiness. These lesions usually have a circular appearance in the beginning, which lead to the name. Dogs can also get bacterial and yeast infections on the surface of their skin, which results in itchiness and usually odor coming from the skin. Sometimes you can see pustules which look like small pimples that give you a good indication that it’s a bacterial infection.
Dog Skin Disease and the Endocrine System
Endocrine diseases can also cause skin disease in dogs. The two most common endocrine diseases that result in skin changes are Cushing’s disease and Hypothyroidism. Cushing’s disease is caused by excessive corticosteroid production by the dog’s adrenal glands. Click here to learn about more symptoms associated with Cushings disease. Hypothyroidism is caused by an underactive thyroid gland which results in a low level of thyroid hormone. Both of these diseases cause hair loss along the sides of the body and can cause a darkening or hyperpigmentation of the skin. In addition, the hair on the tail can fall out resulting in a “rat tail”. Special blood tests are used to determine if either of these diseases is present. Rarely, sex hormones can play a role in hair loss that can look similar to the above endocrine diseases and spaying or neutering may resolve the problem.
Dog Skin Disease and the Immune System
Finally, immune-mediated skin disease in dogs occurs when the body attacks its own skin components, resulting in severe flakiness, crusting, or ulcerations. There are several immune-mediated diseases which are differentiated from each other by the appearance of the cells on a biopsy sample. Flakiness or crusting is usually observed around the eyes or ears, across the bridge of the nose, or on the footpads.