PRA: Progressive Retinal Atrophy In Dogs
The term “Progressive Retinopathy” (or just “Ret” for short) refers to a group of inherited eye diseases that cause the retina to degenerate over time. These diseases are characterized by a gradual loss of visual acuity and eventually blindness. There are three types of these disorders: Type I, which affects the rods; Type II, which affects the cones; and Type III, which affects both. All three types affect different parts of the retina, but they all result in a similar decline in vision.
These diseases occur most often in older individuals, especially those over age 50. They tend to run together in families and affect mostly males. However, there have been cases reported where females were affected as well. Most cases are diagnosed when the disease is detected during routine eye exams.
In general, dogs develop symptoms between ages 5 and 10 years old. The onset of symptoms usually occurs within weeks or months after birth, although it may take longer if the puppy was born prematurely. Symptoms typically begin appearing around age 2 years, but they can appear at any age in some breeds such as Golden Retrievers and Shih Tzus.
PRA is different from other eye diseases in that the loss of vision occurs slowly and gradually. It’s important to begin treatment right away to prevent vision loss, but most dogs with PRA don’t experience complete blindness. Instead, they develop a “tunnel vision” in which they can still see light and shadows but not much detail. This tunnel vision begins in the center of their visual field and moves out until the dog can only see directly in front of itself.
There is no treatment that can stop the disease from getting worse or restore vision that has already been lost. The goal of treatment is to prevent your pet from getting injured due to limited vision by keeping it from running into things or tripping over objects on the floor. If this happens, take your pet to the veterinarian right away since injuries caused by falls can be serious or even life-threatening in smaller dogs and puppies.
Your veterinarian may recommend retinal injections, vitamin supplements or different types of medication. It’s important to closely follow all of your veterinarian’s recommendations. It’s also important to keep in close contact with your veterinarian since the treatment plan may need to be adjusted at any time, especially as the disease progresses.
Puppies that are born with PRA typically have severe disabilities and don’t live very long. However, in some cases puppies may be able to lead reasonably normal lives. Sadly, there have been reports of dogs living comfortably with PRA for several years. As an owner, it’s especially important to keep your pet safe from injury since injuries can be more serious or even life-threatening in dogs with limited vision. Also keep in mind that many of the medications used to treat PRA are also used to prevent further vision loss in dogs with normal eyesight.
This means your pet may experience side effects such as drowsiness, nausea or temporary blindness after taking the medication.
Progressive renal dysplasia, also known as kidney failure, is a miserable way for your pet to suffer from a serious and life threatening disorder. There are many different forms of the disease and all of them will result in kidney failure if it is not properly managed. Kidney problems can be very stressful for you and your pet, but it’s important to remember that this disease is 100% treatable and manageable as long as you follow your veterinarian’s recommendations. Treatment for kidney disease usually consists of a combination of three things:
In some cases your veterinarian may also recommend a low protein diet or even supplemental vitamins, but these choices are up to your veterinarian. There’s no easy way to say this, but the fact is that kidney failure is a progressive and ultimately fatal disease. In other words, it gets worse and then it kills your pet. The goal of treatment is to keep your pet comfortable and quality of life as long as possible. If your pet is suffering from kidney failure, it’s very important that you keep follow up visits with your veterinarian since the disease can progress at any time.
Your veterinarian may recommend blood work to monitor the health of your pet’s kidneys at every visit. This will allow your veterinarian to see if the treatment plan is working or if it needs to be changed. In some cases, it may be possible to delay the need for dialysis or even prevent it completely.
Kidney dialysis is not a cure and it’s not a pleasant way to spend the final days or weeks of life. It’s also very expensive and most pet insurance policies will not cover the procedure. Only pursue this option when your pet can no longer urinate on their own or has kidney failure secondary to another disorder that can’t be treated (ex. cancer). With that in mind, here’s what you need to know about kidney dialysis:
In cases of severe kidney failure, your veterinarian may recommend that you consider kidney dialysis. This is a complicated and often frustrating procedure and is usually not the first line of treatment for pets with failing kidneys. In fact, many pets are not candidates for this treatment simply because their health is too poor and their bodies are unable to handle the stress of the dialysis process.
Sources & references used in this article:
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- A frameshift mutation in golden retriever dogs with progressive retinal atrophy endorses SLC4A3 as a candidate gene for human retinal degenerations (LM Downs, B Wallin-Håkansson, M Boursnell… – PloS one, 2011 – journals.plos.org)
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