Introduction
Two forms of lupus occur in companion animals: systemic lupus erythematosus (SLE) and discoid lupus erythematosus (DLE). If your cat is diagnosed with lupus, the treatment plan will depend upon which of these forms of the disease your animal has. The effects of and treatment protocols for each type of lupus are very different. However, they both are caused by an autoimmune disorder which essentially causes the cat’s body to attack itself.
Treating Systemic Lupus Erythematosus
SLE is rare but probably underdiagnosed in cats. It cannot be cured. Persians, Siamese and Himalayans are predisposed. The goals of treating SLE are to resolve the clinical signs of the disease and prevent progressive renal or other organ failure. Because effects of the disease naturally wax and wane, not all cases need to be treated aggressively at all times.
Cats suffering from severe, acute effects of SLE may need to be hospitalized for initial management until the condition can be stabilized. Enforced rest and a protein-restricted diet are hallmarks of initial treatment. A number of drugs are available for use in acute cases, including corticosteroids to reduce inflammation and suppress the abnormal immune reaction, and non-steroidal anti-inflammatory medications, commonly called “NSAIDs.” NSAIDs and steroids normally are not given in combination because of the increased risk of gastrointestinal ulceration. Cats should not be given azathioprine, because cats tend to have adverse reactions to this drug. Your veterinarian will decide upon the appropriate medical protocol for your cat.
In order to alleviate the dramatic, progressive, unpredictable and often painful effects of SLE, chronic treatment is designed to suppress the cat’s immune system (which is essentially attacking itself). Often a combination of steroids and other immunosuppressant drugs is used to combat the effects of lupus. Supportive care, enforced rest and dietary restrictions are important components of treatment. In most cases, treatment (or more accurately, management) of SLE must be continued for life, although doses of medication can be tapered if remission occurs.
Long-term immunosuppressive therapy has adverse side effects that must be taken into account when designing a treatment protocol for cats with SLE. These include bone marrow suppression and increased risk of localized or systemic infection, such as bronchopneumonia or urinary tract infections, among other things. Weight gain is also common with steroid use. Unfortunately, use of immunosuppressive drugs is the only viable method for managing SLE. There is no surgical option. Regular physical examinations, urinalyses and blood tests should be conducted on an outpatient basis to monitor the side effects of immunosuppressive medication. Affected animals should not be bred. Given its unpredictable and progressive course, the prognosis for cats with SLE is guarded to poor.
Treating Discoid Lupus Erythematosus
Like SLE, discoid lupus erythematosus cannot be cured. However, it is more manageable than the systemic form of the disease. It is one of the most common immune-mediated skin diseases of companion animals – common in dogs and rare in cats. The goal of treatment is to control and resolve the skin lesions that accompany this disease. DLE is a variant of lupus that primarily affects the face - particularly the hairless areas of the nose. Treatment protocols can include oral antibiotics, topical ointments, oral vitamin E, oral essential fatty acid supplements and oral or topical steroids.
Clinical signs of SLE and DLE usually worsen with exposure to ultraviolet light. Accordingly, affected animals should be kept out of the sun as much as possible. Owners can apply waterproof, high SPF sunscreen to affected areas as well.
As with SLE, cats with DLE should be checked by a veterinarian regularly to assess progression of the disease and to monitor the success of treatment. Affected cats should not be used for breeding. Unlike SLE, the prognosis for cats with DLE is fairly good, since this disease is progressive but not life-threatening and is not common in cats. Those cats that do develop DLE often go into remission, making chronic immunosuppressive therapy less commonly necessary. Moreover, cats with DLE usually feel fine, even though the condition can be disfiguring.