What's the deal with DLE?

Discoid lupus erythematosus is an immune-mediated in dogs that causes changes to appearance of the nose and possibly the bridge of the nose. It can also affect other parts of the face, including the ears. Thankfully, this condition is limited to affecting the skin.
Clinical signs include loss of pigmentation of the color of the nose, scaling and ulceration.
There are several other conditions that can cause similar changes – ranging from bacterial infections to systemic autoimmune conditions, fungal diseases and neoplasia – so this condition requires a biopsy for diagnosis.
Treatment often involves oral and topical immune-suppressing medications. Tetracycline antibiotics (such as Doxycycline) and vitamin B3 supplements (niacinamide) are also used. Vitamin E can be helpful as well. Avoiding exposure to sunlight is also beneficial. This condition can go into remission if an appropriate treatment is followed as recommended!
References:
https://www.petmd.com/dog/conditions/skin/c_dg_dermatoses_depigmenting_disorders
Tilley, L. P., & Smith, F. W. (2005). The 5-minute veterinary consult: Canine and feline. Philadelphia: Lippincott Williams & Wilkins.
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