Causes of uveitis in dogs: 102 cases (1989-2000)

Uveitis is one of the most common ocular diseases and one of the most common causes of blindness in dogs. The purpose of this retrospective study was to correlate the signalment, history, clinical signs and ophthalmic findings of dogs with uveitis with the underlying etiology. We conducted a retrospective study of 102 dogs presented to the NCSU-VTH from 1989 to 2000 with clinical signs of uveitis. Medical records of dogs presented for uveitis were reviewed. Dogs were included in the study only if a complete diagnostic work-up database was collected, if sufficient follow-up was documented, and if the uveitis was not secondary to trauma or a hypermature cataract. The mean age +/- SD of all dogs in this study was 6.2 +/- 3.6 years. There were 33 intact and 16 castrated males, and 14 intact and 27 neutered females. Fourteen breeds were represented, with the Golden Retriever (n = 14) most common. Fifty-nine dogs (58%) were diagnosed with idiopathic/immune-mediated uveitis, neoplasia was diagnosed in 25 dogs (24.5%) and 18 dogs (17.6%) were diagnosed with infectious causes of uveitis. Aqueous flare was the most common clinical sign, occurring in 88 dogs (86%). The most common infectious organisms associated with uveitis in the dogs of this study were Ehrlichia canis (n = 7). Lymphosarcoma (n = 17) was the most common neoplasm. In approximately 60% of dogs presenting for uveitis an underlying cause was not found, and a diagnosis of immune-mediated or idiopathic uveitis was made. However, approximately 25% of dogs had ocular and/or systemic neoplasia (with 17% of cases having lymphosarcoma) and 18% with an underlying infectious cause for uveitis. Because of the high percentage of systemic disease associated with uveitis in dogs, extensive diagnostic testing is recommended before instituting symptomatic anti-inflammatory therapy.