Chronic kidney disease (CKD) in cats, which is sometimes called chronic kidney failure, is a fairly common condition, especially in felines that are seven or older. In fact, it’s such a frequent diagnosis that many veterinarians recommend CKD screenings as frequently as twice a year for older kitties to help ensure the illness is caught and treated as early as possible.

There is good and bad news when it comes to CKD. The bad news is that it’s incurable — once a cat has it, she has it for life. However, the silver lining is that it’s a highly-treatable disease, and the sooner your fur baby is diagnosed and prescribed treatment, the more likely she is to live a longer, more comfortable life.

What Is Chronic Kidney Disease in Cats?

In order to understand why CKD can be a dangerous diagnosis for a cat, it’s important to understand what the kidneys do when they’re healthy. As part of her renal system, your kitty’s kidneys:

  • Filter harmful substances out of the blood
  • Produce and filter urine, and then send it to the bladder for excretion
  • Balance the body’s fluid and electrolyte levels
  • Produce erythropoietin hormones, which prompt bone marrow to create red blood cells

CKD causes the kidneys to lose their ability to perform these important functions over a long period of time. If your cat falls ill with CKD, she may only experience subtle symptoms at first, but over time, her kidneys will begin to fail if she isn’t treated. End-stage kidney failure is difficult — and sometimes impossible — to recover from.

What Causes Chronic Kidney Disease in Cats?

There are several known causes of CKD:

  • Tumors, which may be cancerous or benign
  • Bacterial infections, like urinary tract infections (UTIs)
  • Chemicals or medications that are toxic to cats
  • Polycystic kidney disease (PKD), a genetic condition for some breeds of cat (like Persians) in which cysts form on the kidneys
  • Glomerulonephritis, in which the blood-filtering glomeruli vessels in the kidneys are inflamed
  • Physical kidney trauma
  • Hypokalaemia, or lowered blood potassium
  • Hypercalcaemia, or elevated blood calcium

However, the causes of most cases are unknown, so even though your veterinarian will be able to tell you if your cat has CKD, they may not be able to tell you why. This may also mean your cat’s treatment will take some trial and error in order to find the most effective approach.

Signs My Cat Has Chronic Kidney Disease

Depending on how far her illness has progressed, your cat could have a number of different symptoms. If you notice any of these issues for more than a couple of weeks — especially if she’s experiencing more than one — take her to the vet for a CKD screening as soon as possible:

  • More frequent urination
  • High volumes of urine
  • Bloody or cloudy urine
  • Urinating outside the litter box
  • Constipation
  • Diarrhea
  • Vomiting
  • Foul breath
  • Increased thirst
  • Decreased appetite
  • Sudden, inexplicable weight loss
  • Increased lethargy
  • Mouth ulcers
  • Pale gums
  • Brown or discolored tongue
  • High blood pressure

How Chronic Kidney Disease in Cats Is Diagnosed

Your vet will first do a physical exam on your cat to look for physical signs of the illness. What they discover during this part of your visit may help them decide which method to use to test your cat for CKD: 

  • A blood test done with a urine test is the most common way to test for CKD. Because your kitty’s kidneys are responsible for the purity of these fluids, it’s a giant red flag when there are problems in both of them. Your vet will look for elevated levels of blood urea nitrogen (BUN) and creatinine in her blood, and they’ll screen for protein, bacteria, and normal dilution levels in urine.
  • Abdominal ultrasounds and X-rays show changes and abnormalities in kidney tissue, including size changes, atypical shapes, and cysts.
  • Kidney tissue biopsies allow the vet to see damage more closely under a microscope.

Treatment Options for Chronic Kidney Disease in Cats

Once you have a diagnosis, your vet will determine the best treatment plan for managing your cat’s health. Remember, there isn’t a cure for CKD, but the right course of treatment will help prevent your furry friend from experiencing complications of the disease and improve her quality of life.

  • A kidney-friendly diet is the most prescribed treatment for felines with CKD. Every cat is different, but this type of eating plan usually includes:
    • Plenty of fresh water, which prevents kidneys from becoming overworked while trying to conserve and purify the water that moves through them.
    • Wet food, which contains water and helps ensure your pet stays hydrated.
    • Protein restriction, because CKD impairs the body’s ability to break down protein, which can lead to harmful substance buildup in the blood.
    • Low amounts of phosphate, which helps prevent the accumulation of excess phosphate levels that can leach calcium from her bones and deposit it into her heart, lungs, and blood vessels, increasing her risk of heart attack and stroke.
    • Antioxidant-rich foods and fatty acids to help reduce and prevent kidney inflammation.
  • Medication may be prescribed to help fill in dietary gaps. For example, potassium supplements enhance the benefits of low-phosphate fare, while angiotensin converting enzyme inhibitors (ACE inhibitors) and angiotensin receptor blockers (ARBs) help lower blood pressure and promote healthy blood flow through the kidneys.
  • Fluids administered via IVs at your vet’s office may be necessary if your cat is severely dehydrated or has serious electrolyte imbalances when she comes in for testing. This will help her body get back into fighting shape so that her other prescribed treatments work more effectively. Your vet may also prescribe at-home injections if your cat is at risk of ongoing hydration issues.
  • Surgery may be necessary for pets with blockages that are worsening their CKD symptoms, such as in the vessels that move blood in and out of the kidneys, or the ureters that transport urine to the bladder. Kidney transplants are done in very rare cases, but not all vets perform these procedures.

Your cat is a beloved part of your family, so learning she has chronic kidney disease can be devastating. Take heart knowing that with the right treatment, some patience, and lots of love, you and your kitty can spend many more happy, healthy years together.