Skin Problems In Dogs: How To Diagnose A Dog's Skin Condition

Skin problems in dogs can be both uncomfortable for the pet and frustrating for the pet parent, especially because the underlying cause can be difficult to determine. Various allergens, toxins, parasites, and other conditions can cause a dog's skin to react. Because there are so many potential underlying causes for skin problems in pets, it is important to consult your veterinarian for a proper diagnosis and targeted treatment.

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Symptoms of dog skin conditions can range from relatively minor to severe. If you notice that your dog is having skin issues, make an appointment with your veterinarian to get to the bottom of the health problem. Some symptoms of common skin conditions include:

• Itchiness
• Excessive licking
• Redness
• Crusts, scabs, sores, or lesions
• Bleeding or oozing
• Hair loss (alopecia)
• Dandruff / excessively dry skin, flaky skin, or scaly skin
• Skin color change
• Skin thinning or thickening

There are many potential causes of skin problems in dogs. The underlying cause of your dog's skin problems cannot be identified at home. You will need to visit your veterinarian for a complete exam and diagnostics. Common skin problems are caused by:

• Parasites, such as lice, fleas, mites, or ticks
• Allergic reaction (food allergies, environmental)
• Bacterial or fungal infections
• Autoimmune conditions
• Endocrine disorders
• Certain types of cancer
• Exposure to irritants

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Your veterinarian will initially ask about your dog's history with skin issues, such as:

• When did they start?
• What symptoms are you noticing?
• Do you notice a pattern (seasonal, etc.)?

Based on your pet's history, they will perform the appropriate diagnostics.

Look for parasites

Most likely, the first thing your veterinarian will want to do is rule out external parasites. Fleas, mites, and ticks can cause itching, redness, or lesions. When the dog scratches or licks the bites, more redness and irritation may occur, leading to a more severe problem. Your veterinarian will look for live fleas or black specks ("flea dirt") on the skin. They may also perform a skin scraping and look under the microscope for certain mites that cause demodectic mange or sarcoptic mange ("scabies").

If parasites are ruled out, your veterinarian might suspect allergic dermatitis, especially if your pet is generally in good health, and the skin condition recurs during a certain season, although some environmental allergies can be year-round. Some dogs with chronic allergies will experience darkening of the skin on their abdomen or armpit area, and others will have chronic ear infections along with their skin issues.

Dogs can be allergic to food, fleas, and substances in the environment, including dust mites, grasses, trees, and molds. Many allergies affecting the skin can be detected via intradermal skin testing at your veterinarian's office. Sometimes, something as simple as giving an antihistamine medication or changing your dog's food or shampoo will clear up dry, itchy skin.

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For skin conditions involving hair loss and crusting, your veterinarian will most likely want to test for fungal infections, like ringworm. They might take a sample from your dog's skin and hair to send to the lab for tests known as a fungal culture, or fungal PCR which is a quicker and more current way of testing.

Oozing ulcers or erosions (or "hot spots") might point to a bacterial infection or yeast infection. These may be as small as a pimple or a larger crater. Sometimes, the bacterial infection is caused by a less serious skin condition that resulted in your dog scratching or licking the affected area incessantly. Your veterinarian might perform a lab test called a "tape prep" to look under the microscope in search of bacteria and yeast. Antibiotics (or anti-fungals in the case of yeast) will usually clear up the infection and heal the sores.

Cancer, an autoimmune condition, or an endocrine issue could be the culprit. Melanoma might be suspected if there's a skin tumor with a color change in one area only. An endocrine disorder, such as Cushing's disease, might need to be ruled out if the skin has become very thin (friable), and symmetrical bald patches are present. Autoimmune disorders, like atopic dermatitis (atopy) or superficial pemphigus, can cause blisters. A suspected endocrine disorder will require special diagnostic bloodwork. On the other hand, if your veterinarian suspects an autoimmune disease or cancer, they will most likely obtain a skin biopsy for lab analysis.

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Treatment for dog skin problems will depend on the cause. For common skin conditions caused by parasites like fleas, mites, or ticks, a preventative (usually topical or oral) will often get rid of the infestation and solve or mitigate the skin disease. For fungal infections, anti-fungal oral medications will most likely be prescribed by your veterinarian. For ringworm, lime sulfur dips might be recommended as well. Antibiotics can cure bacterial skin infections. Omega-3 fatty acid supplements may also be used.

There are other targeted treatments available if your pet's skin problems are determined to be caused by endocrine disease, autoimmune issues, or melanoma. You will need to visit your veterinarian to determine the cause and proper course of treatment.

Skin problems in dogs are relatively common, but they can be challenging to diagnose, as there are myriad causes for dog skin issues. If you notice that your dog's skin is red, itchy, or crusty or has open sores or if your dog is losing hair, it is important to have your pet examined by a veterinarian to get to the bottom of their skin issues. The veterinarian will perform a variety of diagnostics that might include allergy testing, skin scrapes, ringworm culture, or skin biopsies. Depending on the underlying condition, treatment can be as simple as an antibiotic or in the case of melanoma, more involved, such as surgery. Rely on your DVM (veterinarian) to determine the cause of your dog's skin issues as well as the appropriate treatment options.