Cutaneous leishmaniasis in a sheep.

A case of cutaneous leishmaniasis in a sheep from the Eastern Transvaal is described. The pinna of one ear was swollen and the overlying skin thickened and diffusely encrusted. Histopathological examination of a skin biopsy revealed a diffuse dermal infiltration of macrophages, plasma cells and lesser numbers of eosinophils and neutrophils, as well as a few multinucleated giant cells. Macrophages, particularly in the superficial dermis, contained large numbers of small basophilic bodies morphologically compatible with the amastigote stage of Leishmania spp. Changes in the overlying epidermis included orthokeratotic hyperkeratosis, pseudoepitheliomatous hyperplasia with a focal erosion and crust formation. No attempts were made to culture the organism.