Skin Lesions

Discoid lupus erythematosus (DLE) in dogs can present with facial lesions or as a generalized variant. In this case study, a 6-year-old dog had a 2-year history of progressive pruritic skin lesions. Skin biopsy was compatible with cutaneous lupus erythematosus. Treatment with doxycycline, niacinamide, and prednisone was started. After 4 months, the dog had not improved and was referred to a veterinary dermatologist. The diagnosis of cutaneous lupus erythematosus was confirmed via skin biopsy, direct immunofluorescence, and routine laboratory testing (complete blood count, urinalysis, serum chemistry panel, and antinuclear antibody testing); coexistent systemic lupus erythematosus was ruled out. Except for the skin lesions, the dog was otherwise healthy. Treatment with dexamethasone and oral cyclosporine was initiated. As insufficient clinical response was noted after 1 month, the dexamethasone was discontinued and ketoconazole treatment started concurrently with cyclosporine. Within 4 months, pruritus and erythema resolved. The dog was considered to be in clinical remission 2 months later. At the time of publication, the dog’s clinical lesions were being maintained with oral cyclosporine and ketoconazole every 3 days.

Commentary

For clinicians who encounter this rare condition, cyclosporine represents an option that has not been reported previously. It is important to stress that the localized form of discoid lupus is far more common than the generalized form. Typically, the localized form does not require oral systemic therapy and can often be maintained effectively with topical steroids or tacrolimus. For those rare cases of generalized discoid lupus, cyclosporine is an option when doxycycline therapy fails. It is also important to stress that in dogs with generalized discoid lupus or cutaneous lupus, clinicians should rule out systemic lupus through further testing including blood counts, serum chemistry panel, urinalysis, and anti-nuclear antigen serology.—William Oldenhoff, DVM, DACVD