Pathology in Practice

摘要

A 7-month-old sexually intact male domestic longhair cat was evaluated because of unusual skin lesions affecting both ears. The cat had been relinquished by its owner to a county animal shelter. No medical history was available.On physical examination, the cat was in good body condition with abnormalities limited to both external ear canals and pinnae. The cat had locally extensive crusted and hyperkeratotic proliferative plaques that filled the external and vertical ear canalsand extended onto 35% to 50% of the proximal concave portions of both pinnae. Lesions were multifocal at the margins. Surface crusts were brown to black and friable; disturbance of the crusts revealed underlying erythematous proliferative tissue with multifocal erosions. Noncrusted areas had a rough surface with barely visible short papillary-like projections in some locations. A thick purulent exudate was present between some of the lesions, and cytologic examination of a sample of the exudate revealed degenerate neutrophils and small to moderate numbers of gram-positive cocci. Via otoscopic examination, the horizontal ear canals were normal in appearance and the tympanic membranes were intact. The lesions neither appeared painful nor were pruritic.An ELISAa for circulating FeLV antigen and anti-FIV antibodies yielded negative results. Serum biochemical analysis and CBC results were within reference ranges. The cat was anesthetized, and multiple biopsy samples were obtained from both ears (Figure 1).