Auricular chondritis in a cat.

A four-year-old male neutered domestic shorthaired cat developed bilateral thickening of the pinnae, with slight curling, intense erythema and pain. No ear canal disease was present. The cat was negative for feline immunodeficiency virus, feline leukaemia virus and feline coronavirus. Biopsy of the ear lesion revealed auricular chondritis. In humans, histologically similar lesions may involve the pinnae, nose, trachea, joints, eyes and heart, and the disease is termed relapsing polychondritis. The cat reported had a history of corneal damage, resulting in corneal vascularisation and opacity, eyelid distortion, necessitating an entropion operation, and radiological evidence of mild cardiac enlargement. The ear disease responded rapidly to treatment with prednisolone and, apart from slight thickening and curling of the pinnae, the cat remained normal and pain-free. After two years, the prednisolone was withdrawn, and there was no recurrence of the condition in a follow-up period of 14 months.