As your dog ages, you probably expect to see a few more gray hairs around their muzzle. If you see white spots on a dog’s nose or white spots on dog skin in a relatively young dog, however, it’s only natural to be concerned.
Vitiligo is a rare skin condition that causes a patchy loss of skin pigment, usually affecting a dog’s face and muzzle. Your dog’s previously-black muzzle may develop pink or white spots, and you may even see gray or white hair growing in these areas.
While this can certainly be a surprising change, there’s good news. Fortunately, vitiligo is only a cosmetic condition. It doesn’t have any negative impacts on your dog’s health, and it usually is not associated with any serious medical conditions.
What is Vitiligo?
Vitiligo is a rare, progressive skin condition that causes harmless lightening of the skin in dogs, cats, and even humans. Affected dogs develop well-demarcated patches of depigmented or white/pink skin, often on the face and muzzle. Fortunately, vitiligo is only a cosmetic issue. The loss of skin pigmentation is not harmful or damaging to affected dogs, though it may be a bit perplexing to their owners.
In most cases, the skin color changes associated with vitiligo are permanent. In some cases, however, dogs may have a waxing and waning course of vitiligo. These dogs may have changes in their skin color over time, with the skin alternating between darker periods and lighter periods.
What Causes Vitiligo in Dogs?
Vitiligo is caused by the loss of melanin (skin pigment) and melanocytes (melanin-producing cells) in the skin. Dark canine skin, such as the skin that is present on the nose and eyelids of many dark-colored dogs, contains large amounts of melanin. Skin vitiligo in dogs leads to the loss of melanin, causing the skin to take on a pink or white color. It is most common in young adult dogs, and most cases are diagnosed in dogs less than 3 years old.
The underlying cause of dog vitiligo is unknown. Vitiligo may have a genetic basis in some dog breeds, including the Belgian Tervuren, Dachshund, Doberman Pinscher, German Shepherd, German Shorthaired Pointer, Old English Sheepdog, and Rottweiler. However, even in those breeds, the genes responsible for vitiligo have not been identified.
Given that vitiligo is primarily a cosmetic disease, it may be unsurprising to learn that most research on this condition has been conducted in humans. Human cases are typically caused by genetic mutations that occur in a number of different genes. Autoimmune diseases and environmental impacts may also play a role in human vitiligo. At this time, it doesn’t seem that vitiligo is associated with autoimmune diseases in dogs.
Symptoms of Vitiligo in Dogs
Vitiligo is characterized by patches of unpigmented skin. These lesions often begin on the face, but they can affect other areas of a dog’s body including the limbs, paws, genitals, and the skin around the rectum.
Pigment loss is often symmetrical, equally affecting both sides of the body. In the early stages of vitiligo, you may notice mild redness or scaling of affected areas. With time, however, this redness resolves and leaves behind healthy skin that is white in color. A dog with vitiligo may also develop gray or white hair within the regions of skin depigmentation.
Signs of vitiligo include:
- Clearly defined regions of skin depigmentation, often starting on the face
- Symmetrical pigment loss
- Mild redness/scaling in early stages
- Lack of inflammation in later stages
- Lighter hair in affected areas
- Non-painful lesions
Diagnosing Dog Vitiligo
It can be tempting to see pigment loss on your dog’s skin and immediately assume that your dog has vitiligo. However, there are a number of other dog skin conditions that can also cause a loss of skin pigmentation, including bacterial infections, autoimmune diseases, and certain types of skin cancer. It is important to see your veterinarian for an accurate diagnosis.
Your veterinarian will begin with a thorough physical exam. Dogs with vitiligo have a characteristic clinical appearance, including well-demarcated areas of skin lightening on the face and other areas of the body. Your veterinarian will also look for evidence of inflammation or infection. Your veterinarian may pay careful attention to your dog’s nose, if it is affected, because a loss of the nose’s normal cobblestone architecture can be an indicator that you are dealing with something more serious than vitiligo.
Next, your veterinarian may recommend a skin cytology. While a skin cytology cannot be used to definitively diagnose vitiligo, it can help rule out bacterial skin infections and some autoimmune diseases. This is an affordable, non-invasive test that will help your veterinarian narrow down possible causes of your dog’s skin depigmentation.
In order to definitively diagnose vitiligo, your veterinarian will need to perform a skin biopsy. This test is performed under heavy sedation or general anesthesia. Your veterinarian will remove a small sample of your dog’s skin and then close the biopsy site with one or more sutures. The biopsy sample will be submitted to a reference laboratory for analysis, and your dog will be sent home for rest and monitoring until the pathology results are received. A biopsy is the most accurate method for diagnosing most canine skin conditions, including vitiligo.
Dog Vitiligo Treatment
There is no single effective treatment for vitiligo.
There are a few reports of successful treatment with a supplement called L-phenylalanine, but many veterinary dermatologists report minimal success with this approach. L-phenylalanine is inexpensive and low-risk, so it may not hurt to try it. However, you should talk to your veterinarian before giving this supplement or any medication that has not been prescribed for your pet.
Some veterinarians may recommend topical steroid creams to treat vitiligo. While this is unlikely to restore pigment to affected areas, it may slow the progression of the condition. However, topical steroids can lead to thinning of the skin and other side effects, so it’s important to discuss treatment with your veterinarian and ensure that the benefits outweigh any potential risks.
Fortunately, vitiligo is a cosmetic condition only. It does not cause your dog any discomfort, nor does it have any impacts on your dog’s quality of life.
How to Prevent Vitiligo in Dogs
Given the suspected hereditary nature of vitiligo, affected dogs should not be bred. Unfortunately, there is no way to prevent vitiligo from developing in any particular dog.