SARDS in Dogs
Causes, Treatment, and Prevention
SARDS in dogs is a mysterious health condition that results in sudden and permanent blindness. The disease attacks the retina, causing irreversible damage. Most owners report that their dog went blind “overnight,” though the condition likely has been damaging the eyes over a period of days to weeks.
What Is SARDS?
SARDS, or sudden acquired retinal degeneration syndrome, occurs in dogs and results in rapid and permanent blindness. The disease is idiopathic in nature, which means veterinarians and scientists have been unable as of yet to determine the cause. The condition typically affects dogs and has not been reported in cats. The blindness caused by SARDS results from a degeneration of the cells in the retina that process light and vision.
The eyes may appear normal, but the dog will be blind. The pupils may have abnormal responses to
light. Affected animals may exhibit only blindness or other additional signs like increased drinking, urination, and appetite.
Symptoms of SARDS in Dogs
Dogs with SARDS will typically go blind very quickly, and it may seem as if it occurred “overnight.” In reality, the dog will typically lose vision over a period of days to weeks. In the beginning, they are able to compensate for their failing vision, and therefore, it may not be apparent to their owners. Once the dog’s vision declines to a point that they can no longer compensate, owners often will report the dog bumping into walls and furniture. Other signs of SARDS in dogs include:
Abrupt loss of vision
Disorientation
Pacing
Getting “stuck” in corners or behind furniture
Being “clingy”
Avoiding stairs or refusing to walk off of curbs
Sleeping more
Being less active
Some dogs with SARDS may also present with signs consistent with Cushing’s disease. Though the link between the two conditions is unknown at this time, these dogs may exhibit increased drinking, urination, appetite, excessive panting, and a pot-bellied appearance.
What Causes SARDS in Dogs?
Unfortunately, the cause or causes of SARDS in dogs remain a mystery at this time. There has been some discussion amongst scientists and veterinarians regarding the fact that an immune-mediated process may be the root cause of SARDS. A similar syndrome in humans called cancer-associated retinopathy may be similar.
Though no particular risk factors are known for the development of SARDS, there is an overrepresentation of overweight, middle-aged or older, small breed, mixed breed, and predominantly female dogs diagnosed with SARDS. The most common breeds affected by SARDS are reported to be miniature schnauzers, beagles, pomeranians, shih tzus, Brittanys, cocker spaniels, dachshunds, Maltese, and pugs.
How Do Vets Diagnose SARDS in Dogs?
SARDS is diagnosed by ophthalmologists using a special tool called electroretinography (ERG). SARDS may be suspected by a dog’s primary care veterinarian after a complete physical, taking a history from the owner, a thorough ophthalmologic exam, and excluding other issues via diagnostic testing. Tests will likely include blood work and possible radiographs or ultrasound examinations.
When examining the dog’s eyes, the veterinarian will start to assess the dog’s vision and visual reflexes. Many different in-clinic tests can show if the dog is visual, and will often yield negative results. The pupil’s response to light will often be slow or absent in the vast majority of dogs with SARDS.
Some dogs suffering from SARDS will have retinal changes that can be seen by a veterinarian with a slit lamp. Often these changes are not visible in the earlier stages of the condition, but become more prominent over time. The blood vessels in the retina may be less prominent, and the tapetum lucidum (the reflective surface of the eye) may be more easily visualized.
A confirmed diagnosis of SARDS is not usually made by the primary veterinarian’s office; confirmation must be made by a board certified veterinary ophthalmologist with specialized equipment. This specialist will be able to perform electroretinography (ERG), which is the only truly definitive way to diagnose SARDS. During this test, a bright light will be flashed into the eye. While this occurs, a highly sensitive machine will record the electrical activity of the retina. A significant or complete loss of electrical activity within the retina yields a definitive diagnosis of SARDS.
Other diseases and conditions of the eye can cause vision loss and retinal changes similar to SARDS. It is imperative to have your dog examined by their primary care veterinarian and a veterinary ophthalmologist to rule out other conditions.
How to Treat SARDS
Unfortunately, there is no effective treatment for SARDS. Once a dog with SARDS loses their vision, there is no way to reverse the blindness. Dogs who also develop increased drinking, urination, and other Cushing's-like symptoms often have these symptoms resolve over time though.
It is also possible that a dog’s vision loss can have other causes besides SARDS, such as an infection, cancer, or autoimmune condition. Many of these issues can be treated, and your primary care veterinarian or veterinary ophthalmologist can guide you.
Prognosis for Dogs with SARDS
Many owners are initially very upset when their dog receives a diagnosis of SARDS. The good news is that dogs are very adaptable and often go on to live a good quality of life. It is important to give the dog time to acclimate to their blindness and to do what we can to make it easier for them.
Dogs with SARDS often do an amazing job of memorizing their surroundings. It is common for these dogs, once acclimated, to run around the house in a manner that no one can even tell they are blind. It is important to keep objects in the house constant and not to leave unexpected hazards in the dog’s path. Dogs with SARDS should always be walked on leashes and aided in navigating the outdoor environment. Extra care should be taken to keep these dogs, and other blind dogs, away from pools, ledges, bodies of water, or other places where they could fall or enter a dangerous environment.
Most dogs with SARDS have an excellent prognosis and go on to lead very happy and comfortable lives. If you have any concerns about helping your blind dog adjust, we encourage you to speak to your veterinarian.
Read Next:How to Care for a Blind Dog
How to Prevent SARDS
Because we do not yet know what causes SARDS in dogs, any way to prevent the disease is unknown at this time.
Frequently Asked Questions
Can SARDS be caused by a toxin?
At this time, we do not know precisely what causes SARDS, but there is no currently known association with a toxin.
Is SARDS painful for dogs?
The retinal degeneration associated with SARDS is not painful for dogs. Typically occurring suddenly and leading to complete blindness over a timespan of a few weeks, this disease may cause some temporary disorientation for the dog, but not pain.
How common is SARDS?
Because there is no central database for collecting the health information of dogs, it is impossible to track all diagnosed cases of SARDS. Though it is not a particularly common disease, the average primary care veterinarian typically may see one or two cases a year.
