[From Tufts November 2011 Issue]
My golden has just been diagnosed with pigmentary uveitis. I never heard of it and wonder how many other dogs may have it. The vet eye doc said it is genetic. Is that true? Could it have been diagnosed before the secondary glaucoma and cataracts have destroyed my dog’s sight? I do not know my 12-year-old dog’s background as he was a rescue from animal control when he was about a year old.
Lake County, Florida
I’m sorry to hear about your dog. Unfortunately, golden pigmentary uveitis (GPU) is one the most common ocular diseases we see in goldens. It is a bilateral inflammation of the uvea (the middle vascular coat of the globe), although it doesn’t occur in both eyes at the same time. It is likely caused by a reaction to pigment (melanin) dispersion. It has been associated with presence of iridocyliary cysts in the back of the iris that most of the time can be seen only with ultrasound biomicroscopy.
It is a subtle disease since it is chronic and may be associated with very mild signs initially, but like a drop of water can carve stone, slowly progressing inflammation can damage the eye in the long term. Cataract and secondary glaucoma are usually the most common complications.
GPU can’t be cured, and cataract surgery is usually discouraged because of severe associated complications. Because of this selectivity in the breed, it is considered to be a likely heritable condition. However, no gene mutation has been identified so far, and I am personally convinced that this is a polymorphic condition, where multiple combinations of predisposing genetic variations are needed for it to develop.
Prevention is at the moment the best option for earlier medical intervention. Veterinary ophthalmologists belonging to the American College of Veterinary Ophthalmologists are checking for the early signs of the disease when performing CERF (www.vmdb.org/cerf.HTML) examinations. The examinations are suggested yearly in purebred dogs.
Stefano Pizzirani, DVM, Ph.D., DECVS, DACVO
Assistant Professor, Ophthalmology