Adjunctive Therapy of Pimecrolimus for Treatment of Facial Discoid Lupus Erythematosus in a Dog

Abstract

A two-year-old, spayed female, 22.5 kg Pungsan was referred with chronic crusts and erosion on the nose. A referring veterinarian prescribed an anti-inflammatory dose (0.5-1 mg/kg/day) of oral glucocorticoids for 5 months, but skin lesions showed no meaningful improvement. A dermatological evaluation revealed a crust, depigmentation, erosion, and erythematous lesion over the nasal planum with a loss of the normal cobblestone texture. Also, firm and multifocal plaques over the thigh, groin, axilla, and dorsum were detected. A cytology examination on the nose, thigh, groin, axilla, and dorsum revealed moderate neutrophilic inflammation and bacterial infection. Abdominal radiography and ultrasonography revealed subcutaneous calcified materials along the thigh, groin, axilla, and dorsum. Calcinosis cutis was suspected because of the adverse effect of previous prolonged corticosteroid therapy. A histopathology examination of the nose lesion revealed moderate to severe degenerative or apoptotic changes of the basal layer and lymphoplasmacytic interface dermatitis. Facial discoid lupus erythematosus (FDLE) was diagnosed based on the history and the clinical, cytological, and histopathological results. Minocycline (7 mg/kg PO q 12 h) and niacinamide (500 mg/dog PO q 12 h) were prescribed as initial treatment. Glucocorticoids were not administered due to the presence of calcinosis cutis induced by previous corticosteroid treatment. After 6 weeks of treatment, the clinical signs on the nose were mildly improved. At this time, topical 1% pimecrolimus cream (twice daily) was initiated, while minocycline and niacinamide were continued at the same dose. The nasal planum markedly improved after 6 weeks of additional treatment, hence minocycline and niacinamide were prescribed for an additional 2 weeks and stopped, and the patient was continued solely on topical pimecrolimus. The dog's skin lesion has been maintained in clinical remission with topical 1% pimecrolimus twice daily for more than 5 months.