My dog's nose started to change color. The veterinarian examined him and took a biopsy sample. The biopsy report came back with a diagnosis of discoid lupus erythematosus. The veterinarian gave me an ointment to put on my dog's nose and told me to watch for skin breakdown. Could you tell me about this disease?
Discoid lupus erythematosus (DLE), also called cutaneous lupus, is an immune-mediated collagen vascular disease that affects the skin and mucous membranes of dogs and cats. Collies, German shepherds, shelties, Siberian huskies, Alaskan malamutes, Brittany spaniels, German shorthaired pointers, and cross breeds between them are the breeds most commonly affected. DLE may strike at any age, and males and females are equally affected.
DLE is a genetic disorder. It is related to systemic lupus erythematosus (SLE), a much more serious disease that affects many organ systems. Veterinarians recognize the possibility that a virus might trigger the onset of clinical signs of DLE in genetically predisposed animals. Additionally, about half of the cases of DLE begin after sun exposure.
The signs of DLE include depigmentation, redness, and scaling of the nose and possibly the lips. At first the nose may appear grayish blue or gray. As the disease progresses, the nose may become eroded and subsequently develop ulcers. Skin breakdown, loss of tissue and scarring may follow. In rare cases the tissue breakdown in the nose may be so severe that hemorrhage occurs. DLE may also produce lesions around the eyes, and on the ears, feet and genitalia.
DLE is diagnosed based on physical exam findings and the results of a biopsy of non-ulcerated skin lesions. Routine bloodwork will usually be normal. Tests for systemic lupus erythematosus and related secondary disorders, including the anti-nuclear antibody test, the LE cell test, and Coomb's test usually will present negative or normal values. DLE must be distinguished from SLE and other conditions involving the skin, including fungal and parasitic infections and allergies.
Treatment in most cases involves the application of topical corticosteroid preparations. Severe cases may require a systemic combination of prednisone and azathioprine, an immunosuppressive drug. Affected dogs should not be exposed to the sun.
I recommend you stay in close communication with your veterinarian and report any changes in your dog's condition. The majority of dogs with DLE have a good prognosis. Unlike SLE, discoid lupus erythematosus is not life threatening.
05/14/01
