Síndrome uveodermatológica : revisão de literatura e relato de caso

Abstract

Uveodermatological syndrome is a chronic autoimmune disease in dogs that affects melanocytes and melanin-forming proteins, inducing dermatological and ophthalmic changes. Factors related to B lymphocytes and tyrosinase, inducing melanocyte apoptosis, autoantibody production, and granulomatous and/or lymphogranulomatous lichenoid inflammation have been implicated as causes. This report aimed to describe the clinical, dermatological, ophthalmic, diagnostic characteristics, and clinical evolution of a case of uveodermatological syndrome in an Akita dog treated at HOVET-UFMT. A 4-year-old male Akita dog was treated at the medical clinic of HOVET-UFMT with a history of sudden blindness about a month ago and a visit to the veterinarian, but with worsening of the condition for a week. On physical examination, the exercises were within normal limits, body score 2, hypopigmentation of the focus and upper lips, and on ophthalmological examination, conjunctival hyperemia, absence of direct and consensual pupillary reflex, and bilateral threat reflex, hypotonia in the right eye, in addition to misshapen iris, moderate cellularity, hemorrhagic foci and bilateral vitreous degeneration and bombé iris in the left eye on ophthalmic ultrasound, leading to the ophthalmic diagnosis of bilateral uveitis. At this time, 1% prednisolone acetate eye drops were prescribed ophthalmically, three times a day for seven consecutive days. Considering the clinical and ophthalmic results, the suspicion was that it was uveodermatological syndrome. To confirm the diagnosis, a histopathological analysis of a skin fragment from the muzzle and upper and lower lips was requested, as well as a diagnosis of exclusion for canine visceral leishmaniasis and hemoparasitosis (Ehrlichia canis and Babesia sp) for differential diagnosis, all of which were negative. A histopathological analysis revealed dermatitis due to histiocytic infiltration and lymphocytes with a lichenoid pattern, in addition to multifocal pigment incontinence, suggesting uveodermatological syndrome. Upon confirmation of the diagnosis, treatment was started with systemic prednisolone and then cyclosporine 5 mg/kg, once a day. The dog developed glaucoma in the right eye, and eye drops based on dorzolamide hydrochloride 2% and timolol maleate 0.5% were prescribed. To treat an immune disease with serious ophthalmic complications, early diagnosis of uveodermatological syndrome is essential to prevent blindness. The delay in diagnosis and initiation of treatment led to blindness due to established panuveitis, and later, glaucoma. Therefore, a uveodermatological syndrome should be suspected in cases of uveitis in dogs, especially in predisposed breeds such as Akita and Siberian Husky, in order to introduce appropriate therapy and consequently, maintain visual integrity.