Kidney (renal) disease in dogs happens when their kidneys stop working properly. Kidney disease may be chronic (comes on gradually) or acute (sudden).

Chronic kidney disease (CKD) is an uncommon illness affecting older dogs. Between 0.1 and 3% of dogs in the UK will develop chronic kidney disease. Dogs of any age, sex or breed can develop CKD. But dogs who get it younger are more likely to belong to specific breeds. For example Bernese Mountain Dogs, Shar-Peis and terrier breeds.

Kidneys carry out a number of essential functions in the body. As dogs get older, their kidneys gradually become less efficient. The reason why this happens isn’t known. There are triggers which can make it happen earlier or progress quicker. These include toxins, infections and other illnesses. There’s no cure for chronic kidney disease. Eventually, the kidneys will fail completely. But the rate of deterioration varies between dogs. Symptoms of CKD can often be stabilised for prolonged periods. Early diagnosis and treatment help achieve the best outcome for the longest time.

What is chronic kidney disease?

Chronic kidney disease means your dog’s kidneys have suffered damage over a long time. The damage can’t be reversed or cured. Eventually, the kidneys will stop working completely.

We often don’t know how the kidneys get damaged. Ageing change is part of the cause, but other factors can include:

• Exposure to toxins: anti-freeze, grapes, raisins, some antibiotics

• Severe or recurrent infections (pyelonephritis, leptospirosis)

• Immune-mediated illnesses

• Some clotting disorders

• Inherited kidney defects in certain breeds

• Certain medicines

Why the kidneys matter

The kidneys are two small organs in your dog’s tummy. They carry out a number of essential functions, including:

• Managing fluid balance in the body by controlling how much urine they produce

• Removing harmful waste and toxins from the blood and getting rid of them in urine

• Sensing and controlling levels of essential minerals and electrolytes (salts) in the blood

• Producing or activating hormones which control blood pressure, calcium metabolism and production of red blood cells

Symptoms of chronic kidney disease in dogs

The symptoms of kidney disease are due to poor control of fluid levels in the body and the accumulation of waste products. Common symptoms include:

• Drinking and peeing (urinating) more

• Losing weight and eating less

• Sleeping more and weakness

• Vomiting from time-to-time

• Having a dull, staring coat

• Developing bad breath (halitosis)

• Having pale gums (anaemia)

Chronic kidney disease isn’t painful in the early stages or when it’s controlled

In later stages of CKD, your dog may develop high blood pressure (hypertension). This is a dangerous complication of the condition.

Symptoms of high blood pressure due to CKD include:

• Head-pressing and staring into space

• Sudden blindness

• Seizures

Call your nearest vet if your dog develops these symptoms.

Are some dogs at higher risk of developing chronic kidney disease than others?

Although we don’t usually know why chronic kidney disease happens, some factors increase your dog’s risk of developing the condition. For example:

Recurrent kidney infections (pyelonephritis)

Inherited abnormalities:

• Glomerulonephritis of Bernese Mountain dogs

• Renal amyloidosis: abnormal proteins damage the kidney in Shar-Pei dogs

• Fanconi syndrome: abnormal salt absorption in Basenji dogs

• Small underdeveloped kidneys (renal hypoplasia or dysplasia) in Miniature Schnauzers, Chow chows, Alaskan Malamute, Standard Poodles, Cocker Spaniels, Shih Tzus, Samoyeds, Doberman Pinschers

• Polycystic kidney disease (rare) in English Cocker spaniels, Beagles, Bull Terriers, Westies and Cairn Terriers

Long-term illness elsewhere in the body. For example sugar diabetes (diabetes mellitus) and heart disease

Certain infectious diseases (leishmaniasis)

Is my family at risk of catching chronic kidney disease?

Chronic kidney disease does not spread between dogs or from dogs to humans.

Diagnosis of chronic kidney disease

Dogs only develop symptoms of CKD when they’ve lost about 70% of their kidney function. Another way of looking at this is that your dog only needs about half of one kidney to look normal. This means we usually only identify CKD in advanced stages.

Vets diagnose chronic kidney disease based on:

Symptoms

Urine tests:

• Urine specific gravity (USG): dogs with chronic kidney disease have very dilute (weak) urine

• Protein levels: diseased kidneys leak increasing amounts of protein into the urine

• Bacterial Culture: bacterial infection can cause kidney disease or make it worse

Blood tests:

• Urea (blood urea nitrogen, BUN) and Creatinine Levels. These raise when kidney function falls by around 60-70%. Both are very useful tests. But things like diet, dehydration and exercise can also influence them.

• SDMA(symmetric dimethylarginine) is a new test. It detects kidney disease early when around 25% of kidney function is lost (rather than 60-70%). This means diagnosing chronic kidney disease one to three years earlier than with BUN and creatinine alone.

• Phosphorus Levels: these increase because diseased kidneys can’t get rid of excess phosphorus from the body.

X-ray or Ultrasound scan to check the shape, size and structure of the kidneys. These tests can detect kidney stones (uroliths, calculi), which can cause chronic kidney disease or make it worse.

Vet treatment for chronic kidney disease in dogs

The goal of treatment is stabilising the condition and minimising further damage. Treatment for severe or advanced chronic kidney disease:

• Fluids to treat dehydration caused by loss of too much fluid from the body as weak urine.

• Treating severe dehydration with fluids and medicine through a drip into their leg

• Stabilising (salt) levels in the blood to maintain nerve and muscle function

• Controlling high blood pressure

Ongoing Treatment:

Special diets- prescription diets for kidney disease contain the correct balance of high-quality protein, salt levels, essential fatty acids and appetite stimulants for cats with CKD

Medications

• Anti-sickness medication to reduce nausea and vomiting.

• Appetite stimulants to encourage eating.

• Medicine to reduce protein loss in urine and minimise weight loss.

• Potassium supplements: essential support for heart and muscle function

• Gastric protectants: to protect the stomach lining

Kidney transplants? Although these are carried out in some other countries, kidney transplants in dogs are banned in the UK

The goal of treatment is to stabilise symptoms and quality of life for as long as possible. Chronic kidney disease is harder to control in advanced stages, especially with raised phosphorus levels and high blood pressure. Successful control is also harder in dogs with other illnesses.

Caring for your dog at home

Most dogs with chronic kidney disease do very well in home care. The following tips will help to keep your dog well for longer and minimise extra trips to the vet.

• Ensure your dog has free access to water at all times

• Ideally, feed a prescription diet for kidney disease

• Always give prescribed medicine and supplements as directed

Giving dogs medication is often challenging, especially if they have a poor appetite. Speak to a vet or veterinary nurse for advice and tips on giving medicine to your dog.

Living with a dog with chronic kidney disease

When the symptoms are under control, your dog can enjoy a full and happy life.

• Encourage your dog to drink as much as possible, adding water to food if necessary.

• Find a prescription kidney diet your dog likes and keep to it.

• Warm food up and add low-salt chicken stock or fish broth to encourage your dog to eat if their appetite is poor.

• Give prescription medicines at the dose and times advised, and in a way that doesn’t stress your dog or you.

Getting your dog to eat is more important than persisting with things which won’t work.

Prolonging a good quality of life is the most important goal.

Chronic kidney disease is progressive. Eventually, kidney damage will be so advanced that the symptoms can no longer be controlled. When this happens, it may be kindest to end your dog’s life peacefully through euthanasia.

You may worry if you’ll know when it is time to say goodbye. It’s a decision that’s very hard to make and distressing for everyone involved. The best any of us can do is focus on what’s best for our beloved companion. We can start by thinking about their quality of life:

• Do good things outweigh the bad?

• Do they still enjoy things and take an interest in life?

• Are other illnesses well-controlled?

• Do you wonder if each day will be the last?

• Are you and they exhausted?

• Is giving medication straightforward or is it a fight that’s worsening quality of life for both you and your dog?

There are guides available online to help you assess your dog’s quality of life.

Talk things through with a vet if you are concerned about your dog’s quality of life.

Assess quality of life

Can chronic kidney disease be prevented in dogs?

We can’t prevent chronic kidney disease when the cause is unknown. But we can minimise the additional risk factors.

• Keep potential toxins out of sight, smell and reach of dogs

• Feed your dog a high-quality diet appropriate for their age and lifestyle

• Ensure your dog gets regular health checks with a vet

• Check your dog’s weight regularly for any unexpected weight loss

• Treat any other illnesses promptly

When to worry about your dog with kidney disease

Call your nearest vet practice if your dog:

• Goes suddenly blind

• Collapses

• Develops severe vomiting or diarrhoea with blood

• Is having a fit or seizure

• Stops drinking altogether

Joii can help with:

• Recognising the signs of chronic kidney disease

• Caring for a dog with chronic kidney disease

• Finding the best diets for your dog with kidney disease

• Giving medicine to dogs who are unwell

• Tempting your poorly dog to eat

• Talking through end of life care

• Understanding euthanasia