Limbal xanthogranuloma in a dog

A 10-year-old female spayed American Pitt Bull Terrier was presented with a slow growing mass on the temporal limbus area of the right eye. Canine nodular granulomatous episclerokeratitis was suspected, and the affected eye was treated with 1% prednisolone acetate ophthalmic suspension and 0.03% Tacrolimus ophthalmic solution. As the lesion did not respond to the medical treatments and continued to grow, the mass was excised by lamellar sclerokeratectomy. Microscopically, the mass was composed of granulomatous inflammation with intrahistiocytic lipids and lakes of acicular cholesterol clefts, histopathology findings consistent with xanthogranuloma. To the authors’ knowledge, this is the first canine report of limbal xanthogranuloma.