Lupus in Dogs

Chihuahua being held by vet.

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Lupus is a disease that affects the immune system of a dog by attacking its tissues. This can be a frightening disease to a dog owner due to the variety of life threatening symptoms it can cause. Because of this, it's important for a dog owner to be familiar with lupus and how it is treated.

What Is Lupus in Dogs?

Lupus is an auto immune or immune mediated disease and there are two main types seen in dogs - systemic lupus erythematosus (SLE) and discoid lupus erythematosus (DLE). Other species, including humans, can also develop lupus.

Discoid lupus erythematosus is also known as cutaneous or facial lupus erythematosus and there are also various forms of DLE that affect the skin, nasal planum, and mucous membranes or gums of dogs. Systemic lupus erythematosus, on the other hand, affects more than just external tissues of a dog. SLE attacks the internal tissues and therefore affects multiple bodily systems and functions. It can vary from dog to dog depending on what part of the body the immune system is attacking but can affect various organs, muscles, the skin, glands and more in a dog.

Systemic lupus erythematosus can cause an array of symptoms since it can affect so many different parts of the body.

Signs of Lupus in Dogs

  • Lethargy
  • Decreased appetite
  • Limping that switches legs
  • Skin redness
  • Skin thinning
  • Skin and lip ulcerations
  • Loss of skin pigment
  • Thinning or loss of fur
  • Enlarged lymph nodes
  • Decreased muscle size
  • Crying when pet

Lethargy and a decrease in appetite may be seen due to the overall discomfort and general unwell feeling in dogs with lupus. Lupus can also cause muscle pain which results in a dog limping and crying when attempting to stand or walk. The limping can switch between legs since the muscle pain is often in more than one place and an attempt to pet a dog's leg that has lupus may even result in a dog crying if it is hurting enough. The muscles also may appear to shrink over time resulting in muscle atrophy.

Skin and fur changes are often seen in dogs with lupus. Thinning of the fur and skin, fur loss, a decrease in pigmentation of the skin, and even skin redness can occur. Many dogs also experience ulcerations on the skin and at the corners of the mouth. Finally, enlarged lymphnodes in the neck, armpits, and other regions may be seen or felt in a dog with systemic lupus erythematosus.

Causes of Lupus in Dogs

Systemic lupus erythematosus is considered to be an immune mediated or auto immune disease. This is because no one knows why the immune system starts attacking the tissues of a dog with lupus. Numerous causes of this condition have been suspected and include genetic factors, viruses, various immunologic disorders, different medications, and even environmental factors but the cause remains unknown.

Diagnosing Lupus in Dogs

Lupus can be difficult to diagnose due to the varied presentation of symptoms. A veterinarian will begin by performing a full physical examination, obtaining a medical histroy, and checking some blood work and running urine tests. The platelets, white and red blood cell counts, kidney enzymes, protein content in the urine, and other results will be analyzed from these tests. If the symptoms and test results indicate a possibility of lupus, a special test called an antinuclear antibody (ANA) titer may be performed. If this test titer is positive, a diagnosis of systemic lupus erythematosus is made.

Treatment of Lupus in Dogs

In order to treat systemic lupus erythematosus, various medications may be used to manage the symptoms and suppress the immune system. Prednisone, prednisolone, azathioprine, and cyclophosphamide are most commonly used in lupus patients but thymosin fraction V and levimasole may also be tried if the other drugs are not helping. If anemia is also present in a dog with SLE, surgical removal of the spleen may be necessary.

Special diets, supplements, and other treatments may also be recommended depending on the specific symptoms being experienced by each lupus patient. If the kidneys are not severly damaged, most dogs are able to be managed long term with medications but if kidney damage is present, it unfortunately progresses into kidney failure and has a fatal outcome.

How to Prevent Lupus in Dogs

Since there may be some genetic factors that can cause lupus, dogs that have been diagnosed with systemic lupus should not be used for breeding. Otherwise, since no one knows exactly what causes lupus, there is no good way to prevent it from occurring in a dog. Some veterinarians recommend supporting the immune system with various supplements or being careful not to over stimulate the immune system with too many medications or vaccinations at one time or for prolonged periods but there is no definitive prevention plan for lupus.

Is Lupus Contagious to Humans?

No, lupus is not a contagious or infectious disease to animals or humans.