Discoid Lupus Erythematosus (DLE) in Dogs: A Cutaneous Lupus Disease

Discoid lupus erythematosus (DLE) is a cutaneous lupus disease that typically has a localized skin distribution. Manifesting as erosive, ulcerative, crusting, and depigmented lesions, discoid lupus erythematosus can be a very uncomfortable and unsightly condition for dogs. Unlike systemic lupus erythematosus (SLE), discoid lupus erythematosus has no systemic involvement and is not life-threatening. If your dog is affected by discoid lupus erythematosus, there are treatments available to help lessen the symptoms and improve their quality of life.

What is Discoid Lupus Erythematosus?

There are two common autoimmune skin diseases in dogs: Pemphigus Foliaceus and Discoid Lupus Erythematosus (DLE). Typical areas affected in dogs with discoid lupus erythematosus include the nose, ears, and periocular regions. It is very rare in cats. The underlying cause is unknown and symptoms can be exacerbated by UV light. Common breeds, such as the collie, Shetland sheepdog, German shepherd dog, and Siberian Husky, are predisposed. Affected dogs are typically young adults or middle-aged. Age ranged from 5 to 12 years (median 9 years) in one study of generalized DLE.

What are the symptoms of Discoid Lupus Erythematosus in dogs?

Discoid Lupus Erythematosus (DLE) in dogs is typically characterized by depigmentation, erythema, scaling, and loss of the normal cobblestone architecture on top of their nose. Skin lesions may expand to involve the bridge of the nose and progress to erosion, ulceration, and crusting. Due to cutaneous vasculature in the nose, ulceration can sometimes result in severe hemorrhage. As the condition progresses, the ears, periocular, and genital regions may also become affected.

How is Discoid Lupus Erythematosus diagnosed?

Skin biopsy is required to diagnose discoid lupus erythematosus (DLE). The procedure can be performed with sedation and involves taking small samples of tissue around the affected areas and lesions. The biopsy sites are surgically closed with sutures and the samples are then sent to a veterinary pathologist for interpretation. As the lesions are frequently secondarily infected, having the samples tested for types of bacteria is also beneficial.

What are the treatments available for dogs with Discoid Lupus Erythematosus?

Canine DLE can be managed with immunomodulatory therapies. There is no one protocol for treating this condition, instead, medications and their doses are selected based on signs or treatment responses as well as preferences from clients/patients alike in order to achieve the best results possible. In certain circumstances, only topical or system therapy works, while in other cases, a combination of treatments is required. UV radiation appears to exacerbate DLE, therefore reducing sun exposure may help manage the condition in certain dogs.

Topical Therapy

Topical treatment can be utilized as the sole therapy for DLE or in conjunction with oral treatment. Topical therapy is particularly beneficial in nasal-region-only DLE situations. Tacrolimus or glucocorticoids can be used for topical therapy and gloves should be worn when applying these medications. After applying, distract your dog with food or a toy to prevent licking away the medication. Ideally, 10 minutes of medication contact time is sufficient.

Systemic Oral Therapy

Systemic therapy may be used either alone or in conjunction with topical treatment. Systemic treatment is particularly beneficial in multifocal DLE cases or localized DLE cases that are difficult to treat topically due to patient-related constraints. Tetracycline and niacinamide (Vitamin B3) are used in combination for their immunomodulatory benefits. Most dogs will respond favorably to this combination but in severe cases, glucocorticoids may need to be used. Cyclosporine can also be used as it is an immunosuppressant.

What is the prognosis for dogs with DLE?

The prognosis for Discoid Lupus Erythematosus (DLE) is generally good. Most dogs respond well to treatment and can have an excellent quality of life even with this condition. However, it should be noted that DLE may not completely resolve as some dogs will relapse after discontinuation of medications or if sun exposure is increased. In some dogs, lesions may persist even with treatment. Dogs that have extensive nasal involvement are at risk for developing SLE and should be monitored closely.

Chronic cases of DLE, especially in dogs with uncontrolled disease, have the ability to convert into squamous cell carcinoma. Monitor your dog for sudden changes to the appearance or if new lesions develop.

Discoid Lupus Erythematosus (DLE) is a type of cutaneous lupus disease that typically has a localized skin distribution. Unlike systemic lupus erythematosus (SLE), discoid lupus erythematosus has no systemic involvement. DLE is diagnosed with a skin biopsy, which is often performed under heavy sedation. Treatment for DLE includes immunomodulatory therapies and in some cases, only topical or system therapy works. UV radiation appears to exacerbate DLE, therefore reducing sun exposure may help manage the condition in certain dogs. The prognosis for Discoid Lupus Erythematosus is generally good. Most dogs respond well to treatment and can have an excellent quality of life even with this condition.