Kidney Disease in Dogs: Causes, Signs & Treatments

You probably understand how your dog's heart and lungs help them thrive, but have you ever wondered what role their kidneys play? Or how you might know if your dog has kidney disease? Understanding these amazing organs and knowing the signs of kidney disease, or renal disease as it’s also known, are really important. Let’s see why.

Your dog has two kidneys, located on either side of their spine just behind where their ribs end. In Chihuahuas, they're about the size of a large blueberry. In Great Danes, they're roughly the size of a human fist. These small organs are so important that your dog (or any mammal) can't live long without healthy ones.

What do kidneys do?

You may know that kidneys make urine, but they do much more than that. Kidneys sustain life by filtering toxins out of the blood through hundreds of thousands of tiny units called nephrons. A kidney nephron contains an important structure called a glomerulus, which purifies blood – sort of like a coffee filter.

The kidneys also contain many sensitive structures that monitor your dog's levels of electrolytes (like salt), toxins, water and other chemicals. These sensors tell the glomerulus what to filter out of the blood and what to keep, according to the body's needs. This is a highly complex process, but, in the end, anything that needs to be filtered out is excreted through the urine. In this way, the kidneys remove toxins (such as drugs) and waste products from the body while balancing the body's pH, water, and electrolytes, including salt and potassium.

The kidneys don’t handle all the waste excretion on their own. The liver also plays a very important role. They’re a great team!

As if all this wasn’t enough, kidneys also:

●   Function as part of the endocrine system, releasing hormones that regulate blood pressure.

●   Produce vitamin D, which helps support strong bones.

●   Control the production of red blood cells.

What is kidney disease in dogs?

Because kidneys filter all the blood in your dog's body, they're also constantly exposed to toxins, infectious organisms, and chemicals that can damage kidney cells. In addition, autoimmune diseases (diseases where the immune system mistakenly attacks healthy cells), trauma, heatstroke, certain hormonal disorders, cancer and even venomous snake bites can damage the kidneys. Some dogs may also inherit kidney issues from their parents.

Kidney disease can be acute (the kidneys fail suddenly) or it can be a chronic (slow and progressive) disease. The problem with catching kidney disease early is that these organs are really good at soldiering on. This often means that the earliest signs are only seen once about 75% of the functioning cells have already been lost. Kidney cells are never replaced.

Signs of kidney disease in dogs

Signs of kidney disease can include:

●   Increased drinking and urination (usually one of the earliest signs)

●   Acute blindness (due to high blood pressure)

●   Dehydration

●   Loss of appetite

●   Vomiting

●   Pale gums

●   Lethargy

●   Diarrhea

●   Seizures

If your dog shows any signs of kidney disease, contact your veterinarian immediately.

Treatment for dog kidney disease

Dogs who experience acute kidney disease can sometimes regain normal kidney function if a vet treats them immediately. Dogs with chronic kidney disease can't be cured, and the condition is typically managed with therapeutic foods and medications.

Treating canine kidney disease

Kidney disease is always a worrying diagnosis but, as we said, acute kidney injury can be treated very successfully in some cases. Developments in nutrition over the years have also made a big difference. In fact, therapeutic diets are the only thing that have so far been clinically proven with the highest degree of scientific evidence to prolong life in instances of kidney disease. These foods have controlled protein and mineral amounts to reduce the workload on the kidneys, and added things like omega 3 oils and antioxidants to reduce inflammation and cell damage. Medications can also make a big difference to quality of life.

However, wouldn’t it be great if we could know that the kidneys were starting to have problems before it was too late? The great news is that we can! Blood tests that look for certain markers of kidney health – namely creatinine, urea and something called SDMA – can pick up the very early stages of renal disease. This gives you a chance to make a real difference to your dog’s lifespan in many cases.

Talk to your vet about how often these tests should be done as part of your dog’s routine healthcare plan. As your dog ages, the frequency of these tests will go up because it tends to be a disease of older animals.

We may not be able to cure chronic kidney disease, but we can work as a team to try and make sure we give your dog the best chance for a long and healthy life.