Clinical and histological recovery of non-thymoma-associatedexfoliative dermatitis in a cat treated with ciclosporin A

摘要

A 6-year-old neutered female European Shorthair cat was referred for chronic,moderately pruritic, alopecic and exfoliative dermatosis that wasunresponsive to antiparasitic, antibiotic or steroidal anti-inflammatorydrugs. The cat presented with truncular alopecia and numerous whitishadherent scales covering the whole body. Differential diagnoses includedsebaceous adenitis, dermatophytosis, demodicosis, exfoliative dermatitisassociated or not with thymoma, drug reaction, feline immunodeficiencyvirus- or feline leukaemia virus-associated dermatoses, epitheliotropicT-cell lymphoma, and yeasts and/or bacterialovergrowth. Blood tests were within normal limits and the retrovirus testswere negative. Skin scrapings, fungal culture, coat brushing and skincytology were negative for parasitic or microbial elements. Radiographsshowed no signs of a thymic mass. Histological examination of skin biopsiesrevealed marked orthokeratotic hyperkeratosis, lymphocytic (CD3 )interface dermatitis and mural folliculitis with absence of sebaceous glandsand occasional apoptotic cells in different epidermal layers. Clinical andhistological findings were consistent with non-thymoma-associatedexfoliative dermatitis syndrome. Ciclosporin A (7 mg/kg) was administeredonce daily. A dramatic improvement was observed after 3 weeks. Ciclosporin Aintake was then progressively spaced out as the clinical signs diminished.Skin biopsies revealed resolution of hyperkeratosis, disappearance of theinflammatory infiltrate and recovery of the sebaceous glands.