Vitiligo is an uncommon skin condition that causes skin to lose its natural pigment, a process called depigmentation. In addition to affecting the skin, vitiligo can also cause hair to turn white. Like humans, dogs and cats can develop vitiligo. Vitiligo is painless and won’t bother the pet at all.
Causes of Vitiligo in Dogs and Cats
The skin contains cells called melanocytes that produce melanin, the pigment that gives skin its colour. Vitiligo occurs when melanocytes are destroyed or die off.
Most cases of vitiligo in pets are hereditary. Certain dog breeds are at a higher genetic risk of developing this condition:
Old English Sheepdogs
German Shorthaired Pointer
Sometimes, vitiligo can be caused by an autoimmune disease. Autoimmune diseases cause the immune system to attack the body instead of foreign substances. With vitiligo, an autoimmune disease attacks and destroys melanocytes.
Other potential causes of vitiligo are stress, exposure to toxins, and neurologic disease. The stress may be due to an underlying medical condition that’s causing discomfort.
Types of Vitiligo
Vitiligo can be categorized into two main types:
Focal vitiligo affects only one area. In dogs, vitiligo that affects only the nose is called “snow nose.”
Generalised vitiligo causes multiple white patches in random or symmetric patterns across the body. In cats, generalised vitiligo can become so extensive that it produces a “cobweb” or “snowflake” appearance of white fur.
Symptoms of Vitiligo
In dogs and cats, vitiligo starts at a young age and progressively destroys melanocytes. As the melanocytes die off, the skin in the affected area turns white or pink. The fur covering the affected skin also turns white.
Vitiligo commonly affects the face first, particularly the nose. Other areas of the face that might lose pigment include the lips and the area around the eyes.
Vitiligo that spreads beyond the face can affect the footpads and other parts of the body. The full extent of the spread, if any, will occur within three to six months of the first appearance of vitiligo. Once the affected areas turn white, they might stay that way, re-pigment, or even wax and wane.
Inflammation, skin lesions, and dander are rare in body areas affected by vitiligo.
After taking a close look at the pet’s skin and fur, the veterinarian will perform a few diagnostic tests. They will take a blood sample to rule out medical causes of vitiligo. The veterinarian will also take a skin scraping from an affected area and look at the skin sample under the microscope. To get an even closer at the skin, the veterinarian might take a skin biopsy, which would show a lack of melanocytes in the affected area.
Treatment and Management
Currently, there are no available treatments for vitiligo that will re-pigment the pet’s affected skin and fur. However, because vitiligo causes no discomfort, the dog or cat will be just fine living the rest of their life with this condition.