Lupus erythematosus is a complex autoimmune condition. Two versions of this disorder are seen uncommonly in dogs, including systemic lupus erythematosus (SLE) and cutaneous (or "discoid") lupus erythematosus (CLE). CLE is sometimes thought to be a milder version of SLE.
In these diseases, a hereditary predisposition of indeterminate modality is responsible for an immunological aberration that allows the body to form protein clusters called immune complexes. When these clusters get trapped in certain tissues of the body they're likely to affect the joints, skin, kidneys, nervous system and the blood itself.
Symptoms and Identification
Arthritis and fever are the most common signs associated with lupus erythematosus, but a great many symptoms can be associated with it. This plethora of potential symptoms means that diagnosis can be extremely elusive. Indeed, that's why the disease is often called "the great imitator."
A diagnosis of lupus erythematosus can be offered if the patient 1) is positive on a blood test for a specific kind of antibody (ANA) and 2) has two or more of the following symptoms: skin lesions, oral ulcers, arthritis, inflammation of the covering of the heart or the lining of the chest cavity, kidney problems, neurologic symptoms and specific changes to the blood cells (low platelets, low red blood cells or low lymphocytes).
Skin lesions like red, scaly areas of swelling on the face and loss of pigment from the nose are common with cutaneous (skin) forms of the disease. Lesions on the ears and thickening of the footpads are fairly common as well. Affected dogs will almost always require biopsy to help confirm the presence of SLE/CLE.
Treatment of the milder, slightly more common CLE version of lupus erythematosus generally requires relatively low doses of corticosteroids like prednisone along with simple nutritional supplements like fatty acids.
For SLE, treatment efficacy is highly variable. While some dogs respond very well to the kind of therapy that might be helpful for less-severe CLE cases, other dogs' conditions are completely unresponsive to medical treatment.
Chemotherapeutics and other immunomodulating drugs are often attempted to no avail in some cases. Euthanasia due to uncontrollable symptoms or drug-related side-effects is not uncommon.
The expense of lupus erythematosus diagnosis and treatment can be relatively low if the condition and diagnosis are straightforward. Unfortunately, they rarely are. Because CLE is relatively mild most cases can be diagnosed and managed for under $500 a year. SLE, however, is another matter. The likelihood that drug expenses or their side effects could mean a large yearly outlay is quite high. Indeed, some dogs might require $1,000 to $5,000 or more just to reach a definitive diagnosis.
Though inheritance modalities have not yet been established it's considered advisable to refrain from breeding affected dogs and their first degree relatives (parents and siblings).
Chabanne L, Rigal D, Fournel C et al: Canine systemic lupus erythematosus. Part II, Compend Cont Educ 21:402, 1999.
Smith BE, Tompkins MB, Breitschwerdt EB: Antinuclear antibodies can be detected in dog sera reactive to Bartonella vinsonii subsp bekhoffii, Ehrlichia canis, or Leishmania infantum antigens, J Vet Intern Med 18:47, 2004.
Stone M: Systemic lupus erythematosus. In Ettinger SJ, Feldman EC, editors: Textbook of veterinary internal medicine, ed 6, Philadelphia, 2005, Saunders.