DISCOID LUPUS ERYTHEMATOUS
Discoid Lupus Erythematous (DLE) is one of a number of autoimmune diseases seen in dogs, in this case affecting the skin. An auto-immune disease occurs when the body’s tissues are attacked by its own immune system. Normally the complex organisation that is the immune system will ‘seek out and destroy’ any invaders, including infectious agents. Patients with autoimmune diseases frequently have unusual antibodies circulating in their blood that instead target their own body tissues.
Discoid Lupus Erythematous is caused by an animals’s own immune system developing an immune response towards antibodies attacking the skin. Usually this occurs on the nose and/or the lips, resulting in lesions (wounds), but in can also be seen on the ears, feet, genitalia or around the eyes. Exposure to sunlight will often worsen these lesions, and may eventually lead to skin cancer.
SEVERITY: Moderate. Can lead to skin cancer if not treated/managed.
DLE results in hair loss, inflamed skin, loss of pigmentation (dark coloured skin lightens, eventually turning pink), scaling and crusting, ulceration, infection, tissue loss and scarring. DLE is most often seen in Collies, German Shepherds, Siberian Huskies and Shelties but it can occur in any breed. Female dogs seem to be more frequently affected than males.
Because most of the clinical signs of DLE can also be caused by other diseases, including other autoimmune diseases, infections and tumours, a definitive diagnosis of the condition can usually only be made after taking ‘punch’ biopsies — small circular tissue samples — of affected areas and assessing the pathology. Biopsies are normally obtained while your pet is under a general anaesthetic.
We will usually initially prescribe antibiotics. These are used for both their antimicrobial effect and anti-inflammatory affects. Vitamin B3 (nicotinamide/niacinamide) may also be a part of your pet’s treatment plan. We may also use immunosuppressive doses of oral corticosteroids. These are usually very effective but side effects will often prohibit their long term use.
Appropriate treatment of DLE will achieve a remission of the disease in about three out of four cases. Following successful treatment, your pet needs to remain on maintenance doses of oral Vitamin E and will need to be kept out of the sun as much as possible. The use of an SPF15+ waterproof sunscreen on exposed skin is also helpful for patients predisposed to DLE.