Auricular Perichondritis and Multifocal Chondromata in an Egyptian Donkey with Droopy

Abstract

A 9-years-old female Egyptian donkey presented with ear drooping, multiple subcutaneous firm nodules (3-7 mm) on the medial surfaces of both ears and intact skin. Furthermore, the ear pinnae were diffusely thickened with subcutaneous induration. The cartilaginous plates of the ear pinnae were intact. The nodular lesions consisted of chronic perichondritis and cauliflower-like outgrowths of hyaline chondrous tissue. Mononuclear inflammatory cells diffusely infiltrated in the subcutaneous tissue and involved the dermal papillae, the dermis and the margin of the cartilaginous outgrowths. Multifocal cauliflower-like chondrous outgrowths emerged from the inner surface of both ears and consisted of irregular lobules of hyaline cartilage with quite regular deeply basophilic chondrocytes and fibrous lobules. T-lymphocytes and macrophages diffusely infiltrated the dermis, and both T-cells and B-cells were densely infiltrated around newly-formed blood vessels in the subcutaneous tissue. On the basis of the gross, histopathological and immunohistochemical findings, chronic auricular perichondritis and multifocal chondromata were diagnosed for the first time in an Egyptian donkey.

Keywords

• Auricular chondritis
• Chondroma
• Droopy ears
• Equine
• Perichondritis