Everything To Know About Kidney Disease In Cats, According To Experts

Causes, symptoms and treatment for kidney disease in cats 🤕

cat with red spot on back

If your cat recently got diagnosed with kidney disease, you might be super scared and not sure what to expect.

The Dodo spoke to Setti Komaied, a veterinary technician at NHV Natural Pet, and Dr. Sarah Wooten, a veterinary journalist and veterinarian with Pumpkin Pet Insurance, to find out everything you need to know about kidney disease in cats.

What is kidney disease in cats?

Kidney disease is when your cat’s kidneys aren’t able to function normally. Healthy kidneys filter toxins from the blood and produce urine.

“Without healthy kidneys, toxins and waste products build up in the blood, causing a variety of health problems,” Dr. Wooten told The Dodo.

There are two types of kidney disease in cats: chronic kidney disease (CKD) and acute kidney failure. Chronic kidney disease in cats is when the kidneys decline over time, while acute kidney failure happens when the kidneys suddenly stop functioning in a few days or weeks.

“If their kidney function declines in a rapid fashion, it is classified as acute kidney failure, as opposed to chronic kidney failure, which happens over time,” Komaied told The Dodo.

Chronic kidney disease occurs most often in senior cats. “CKD is mostly seen in cats of 7 years of age and older, though it can happen in any age of cat,” Dr. Wooten said.

Cats can develop acute kidney failure at any age, since it happens rapidly and doesn’t involve a long progression (for example, it can be caused by eating something toxic or by trauma).

What causes kidney disease in cats?

There are a number of causes of kidney disease in cats, but vets can’t always determine a cause for every cat.

Here are some potential causes of kidney disease in cats, according to Komaied and Dr. Wooten:

  • Genetics
  • Ingestion of poisonous items
  • Medications
  • Trauma
  • Bacterial or viral infections
  • Polycystic kidney disease (an inherited disease that causes cysts to form in the kidneys)
  • Glomerulonephritis (inflammation of the kidney filters)
  • Tumors
  • Amyloidosis (the buildup of protein in the kidneys)

Symptoms of kidney disease in cats

With chronic kidney disease, the early symptoms are often hard to spot. They can seem like normal signs of aging, which makes it hard to diagnose during the early stages.

“The tricky part about CKD is that the symptoms develop gradually over time, and they are subtle, and by the time owners notice a difference in their cats, it is often advanced in disease because it is estimated that 75 percent of the kidneys have to shut down before the cat shows any symptoms,” Dr. Wooten said.

Since kidney disease can be hard to catch, if you notice any of these symptoms, you should take your cat to the vet to get checked out:

  • Weight loss
  • Dull coat
  • Increased thirst
  • Increased urination
  • Urinating outside of the litter box
  • Lack of appetite
  • Lethargy
  • Weakness
  • Bad breath
  • Vomiting

How is kidney disease in cats diagnosed?

To diagnose kidney disease, your vet will perform blood and urine tests to see how much waste products and toxins the kidneys are filtering out. They’ll look at the concentration of blood urea nitrogen and creatinine in your cat’s blood, and they’ll look at the pH, protein levels, bacteria and blood cells in his urine. If the levels of any of these are too high, your cat might have kidney disease because it means that his kidneys aren’t filtering out the waste like they’re supposed to.

Sometimes, vets will also perform ultrasounds and X-rays and check your cat’s blood pressure.

In recent years, a new test has been developed, called symmetric dimethylarginine (SDMA), that’s more sensitive and is able to help vets catch kidney disease sooner, which allows them to put together a plan to slow the progression of the disease, Dr. Wooten said.

To find out which stage of kidney disease your cat’s in, your vet will use ​​The International Renal Interest Society staging, which helps vets determine the stage of the disease based on creatinine levels and SDMA.

How to treat kidney disease in cats

Kidney disease in cats can’t be cured, so treatment is focused on managing the symptoms and slowing the progression of the disease. (Although, acute kidney failure may be able to be reversed if it’s diagnosed as soon as possible.)

“Depending on the stage of the kidney disease, the kidney functions can be well managed with a balanced diet, supplements and vet [prescribed] medications,” Komaied said.

Treatment for kidney disease usually includes the following:

  • Diet change — Your vet might recommend switching your cat to a senior cat food, or they may prescribe a therapeutic kidney food if he’s in the early stages of kidney disease. “Cats diagnosed with kidney disease should eat a diet that contains highly digestible protein that meets or exceeds minimum standards, is restricted in phosphorus and high in omega-3 fatty acids,” Dr. Wooten said.
  • Blood pressure medication — “Cats that suffer from severe kidney problems tend to have high blood pressure that puts undue stress on internal organs, including the heart, lungs and retinas,” Dr. Wooten said. If your cat has high blood pressure, your vet will prescribe a blood pressure-lowering medication.
  • IV fluids — Your cat might need IV fluids to help with dehydration. If your cat’s dehydrated, you should also try to encourage him to drink more. A cat water fountain can help, and you can try feeding your cat wet food, which contains more water than dry food.
  • Phosphate binders — High phosphate levels damage the kidneys, so some cats need medications to bind phosphate and reduce the amount in their bodies.
  • Potassium supplements — Cats with kidney disease often have low potassium levels because they go to the bathroom more frequently, and potassium comes out in their urine, so your cat may need potassium supplements.
  • Anti-nausea medication — Some cats experience nausea with kidney disease and need anti-nausea medicine to help them regain their appetite.

Life expectancy for cats with kidney disease

The life expectancy for cats with kidney disease will vary depending on when the disease is diagnosed. For cats who are treated early on in the disease, the outcome is usually better. But many cats can still live for a good amount of time with kidney disease as long as they receive treatment.

“The good news is many cats can live for years with this condition with the right support,” Dr. Wooten said.

Your cat getting diagnosed with kidney disease can be super scary, but if you take your cat for regular checkups, he’ll hopefully get diagnosed early, which will lead to a better outcome. And if you follow your vet’s treatment plan, your cat can most likely live for many more years.