Dog Skin Diseases

Dogs, just like people, can have a variety of skin problems. Some dogs have sensitive skin that is more prone to allergies or other skin diseases. Just because your dog's skin is covered in a coat of fur does not mean that the skin is safe. Always be sure to keep your dog safe from parasites and allergens, and if he still exhibits skin problems, have him examined by a veterinarian to determine if he has a hormone imbalance or an autoimmune disease.

Allergic

Allergic reactions leading to skin diseases can be induced by several things including pollens, parasites and environmental factors. Canine atopy is a skin disease caused by exposure to seasonal pollens. It results in severe itching, which can lead to secondary infections. Allergic contact dermatitis is caused by repeated exposure to an allergen that causes a rash and skin irritation that not only occurs at the point of contact but that can spread throughout the skin.

Parasitic

Parasites are a common problem that can cause a variety of skin irritations in dogs. The most common parasite is fleas, which cause itching and therefore scratching. Fleas can lead to flea allergy dermatitis which manifests as red bumps, similar to a rash, that are very itchy. Excessive scratching of fleas can lead to a secondary skin infection.

Grubs or fly-larvae can cause cyst-like lumps under the skin. Chiggers are small red, yellow or orange bugs that can cause severe skin irritation, especially between the animal's toes. Sarcoptic mange, caused by a tiny mite that burrows under the skin, is an intense inflammatory reaction that illicits constant scratching, leading to hair loss and skin damage.

Hormonal

Many dog skin diseases are caused by hormone imbalances. They includes hyperestrogenism (an excess of estrogen), which causes bilateral symmetrical hair loss; hypoestrogenism (too little estrogen), which causes the skin to be very smooth and soft but the coat of hair to be very thin; and hypothyroidism, which causes the coat to be very thin.

Autoimmune

There are many autoimmune (meaning the dog's own immune system is attacking its body) diseases that affect the skin in a variety of ways. Pemphigus foliaceus is a disease that causes red skin patches that turn into pus-filled blisters. It often occurs on the foot pads ,which can become thick and cracked. Nodular panniculitis causes lumps similar to in size to marbles to spread under the skin along the back or sides. These lumps may pop and drain, causing scar tissue to form. Toxic epidermal necrolysis is a very severe and painful dog skin disease. It starts with ulcers on the skin, mucous membranes and foot pads and can result in large portions of the skin peeling off.

Treatments

The treatment for these skin diseases will depend upon the underlying cause. For parasites such as fleas, the dog must be treated with a shampoo or a dip. In addition, the yard and household should be treated with pesticides available at retail outlets to assure all fleas and their eggs are killed.

For dogs with allergies the first step is to try to avoid the allergen. However, there is also a variety of treatments, including topical treatments such as shampoos to soothe the skin, antihistamines, steroids and immunotherapy (similar to an allergy shot). The autoimmune disease may be treated using steroids or high doses of immunosuppressive drugs.

References

• Dog Health
• MedLine Plus: Fleas
• Dr. Dan

Resources

• Pet Education