Kidney Disease in Cats: Things You should Know

kidney disease

Kidney disease is among the most dreaded illnesses that pet parents can see their beloved cat go through. Kidney failure in cats can be tough to deal with, especially with no ideal cure for it yet. If you, too, have a cat that you suspect may be going through the same, then we have compiled a short guide to help you with the steps to take. 

What is a kidney disease in cats? 

In a cat with kidney disease, the kidneys are unable to perform their functions normally. Kidneys normally perform three tasks, such as elimination of the protein wastes, urine production, and balancing levels of water, acids, and salts in the body. With kidney failure, their ability to do any of these tasks is compromised. Kidney failure can be further categorized into two types- acute and chronic renal failure. 

Acute Kidney Failure

The development of acute renal failure is generally sudden, not taking more than a few days or weeks. Common causes of the development of acute kidney failure include, but are not limited to:

  • Trauma due to bursting of the bladder or injury to the pelvis
  • Kidney infection
  • Poisons from toxic plants, pesticides, human medications, and even cleaning fluids. Some substances are so dangerous (such as ibuprofen) that even one tablet can lead to kidney failure.
  • Heart failure from low blood pressure that decreases the flow of blood to the kidneys
  • A blockage affecting blood flow to the kidney and urine out of it

As far as acute kidney failure in cat prognosis goes, there are good chances of reversal if it is detected in time. 

Chronic Kidney Failure

Chronic kidney failure is more dangerous without an exact cause. When the nephrons, which are the working units of the kidneys, undergo some serious damage, chronic kidney failure begins to develop. This injury can be from acute kidney failure, any infection, genetic diseases, or even from a long and poorly managed inflammation. 

What are the signs that my cat may be suffering from kidney disease (failure)?

It is vital to diagnose your cat with kidney disease as soon as they begin. Early diagnosis increases the chances of survival and improvement of the overall condition by a significant factor. Here are some of the signs that you should look out for. Do get your cat checked if you notice your cat showing any of these.

Urinating frequently

Contrary to what you may think, urinating too frequently could signal that your cat may have kidney failure. It means that it is not able to retain water. Another similar sign is frequently urinating outside its litter box. In a case of kidney failure, even though urination may be frequent, the toxins will not be filtered out.

Thirst and drinking high amounts of water

In continuation of the first one, your cat will start to drink large amounts of water to replace the fluids that it is losing. 

Bacterial infection in the kidney and bladder

As the urine becomes more diluted, chances of developing bacterial infections also go up. Any such infections in the kidney and/or the bladder could be a sign of kidney disease.

Increased lethargy

With dehydration, cats will feel more lethargic. They lose a lot of energy and would just rest most of the time. Kidney failure also increases the content of waste products like urea and creatinine in the blood, which makes them feel sick. 

Lack of appetite

Kidney failure leads to a lot of metabolic changes in a cat, which leads to loss of appetite too. Chronic kidney disease has drastically reduced appetites. It also increases the risk of ulcers, abdominal pain, and gastrointestinal irritation. 

  • Diarrhea, vomiting or cloudy urine
  • Tongue color changed to a shade of brown
  • Ulcers on tongue and gums
  • Bad breath

What should you and should not feed your cat?

If your cat has kidney failure, then managing its diet should be your topmost priority. In kidney failure, the kidneys will not be able to filter the toxins, which makes it important to decrease their intake altogether. In addition to that, kidney failure also leads to rapid dehydration. Both these factors can be managed to a large extent if a proper diet is followed. Food containing high water content helps in battling dehydration. A diet that has moderate quantities of high-quality protein ensures that there are fewer toxic products like phosphorus and urea produced. With that aim, let’s go over some of the elements that must (or must not!) form a part of your cat’s diet if it is battling kidney failure.

Water – Include

Kidneys that have lost normal functioning capabilities are not effective in removing waste products through urine. It makes urine less concentrated and has higher contents of water. Ensure that you provide your cat with a lot of freshwaters. Change its water bowl multiple times each day and ensure its cleanliness. Some pet parents even use a running water fountain to increase their pet’s interest in water.

Protein – Limit

The progression of chronic kidney failure can be controlled by giving your cat less dietary protein. With less protein, the work that kidneys must-do for removing the by-products like urea associated with it also decreases. Preservation of this kidney function is vital to ensuring the longevity of your cat.

Sodium – Limit

Like protein, sodium also places a lot of workload on the kidneys. Limit the amount of sodium in your cat’s diet. It will also help you to manage your cats’ blood pressure. 

Phosphorus – Limit

Limiting the content of dietary phosphorus helps to delay the progress of Chronic Kidney Failure. Both protein and phosphorus contents are relative to each other, so limiting the former will help you with the latter as well.

Omega-3 fatty acids – Include

They promote the synthesis of compounds that lead to inflammation, causing issues of the kidneys to go through oxidative stress. Or in simpler terms, it decreases the spread of Chronic Kidney failure, decreasing the protein leakage from the kidneys. 

Kidney failure diagnostic techniques

The first thing that your veterinarian will do to check your cat for kidney failure is a physical exam. It is a good idea to take your cat for regular physical examinations to protect it. These can serve as the baseline for later. With a precise abdominal palpitation, the vet should be able to determine any irregularity in the shape or size of the kidneys (too small or big); asymmetry between the two; pain big); asymmetry between the two; pain in the kidneys and any stones in the urinary tract. 

A few other physical tests that help in finding out kidney failure include:

  • Lower than normal body temperature
  • Dry gums and skin tenting, which indicates dehydration
  • Pale gums
  • Weight loss
  • Ocular hemorrhage or even blindness caused by hypertension (high blood pressure)

In addition to these tests, there are other ways to diagnose kidney disease. The most common ones are what we will talk about next.

CBC- Complete Blood Count

A CBC can help in detecting anemia (low red blood cell count), or an increased count of white blood cells. A higher count of white blood cells indicates infection, inflammation, or stress.

Urine analysis

A urine analysis to determine its quality will help before prescribing any treatment. 

Diagnostic imaging

In this, ultrasound and x-rays help to determine any changes in the shape, size, or asymmetry in the kidneys. Diagnostic imaging is also useful to detect irregularities in the urinary tract.

Blood Pressure 

High blood pressure is a common symptom of cats suffering from kidney failure.

Thyroid Testing

The symptoms of hyperthyroidism and kidney failure are often similar. Hyperthyroidism can affect older cats, so the veterinarian may test for that to rule it out. 

Treatment and management of kidney failure in cats

Completely reversing the damage caused by kidney failure is not possible. However, even if the kidneys are completely worn out, and revival is not possible, there are ways to ensure that your cat continues to live for several months or even years, as seen in certain cases. 

There are two phases to such treatment.

Phase 1

The first phase involves restarting your cat’s kidneys. Large amounts of fluids are given to the cat intravenously, to flush out its kidneys. Known as diuresis, this stimulates the nephrons in the kidneys to work again. In a case where there are enough such functional cells alive, then there is a good chance of meeting the body’s waste removal needs. This fluid therapy also helps to provide the body with electrolytes such as potassium. It is also beneficial in controlling diarrhea, vomiting, and providing the required nutrition.

From this method, three possibilities can occur:

  • Kidney function may restart, and go on for anything between a few weeks to few years
  • Renal function is restored but stops once the treatment is stopped
  • Kidney function does not restart

There are no reliable tests at present that can help to know the outcome of this treatment before. In case your cat starts to show improvement, then it is not the end of the treatment. The damage that has occurred is permanent. Home treatment of kidney failure in cats is the next part of the treatment. 

Phase 2

In phase 2, the aim is to keep the kidney function intact for the longest possible time. A few things that are a part of it are:

Diet management

A low protein and phosphorus diet that isn’t acidified. It decreases the work that kidneys have to do and keeps blood levels near-normal. Commercially prepared food options to suit these needs are available.

Potassium Supplements

Excess urine production decreases potassium, which further lowers kidney function. Supplements for potassium are thus crucial to maintaining the kidneys.

Drugs to combat other symptoms

The veterinarian may prescribe drugs for regulating the blood pressure, regulating calcium levels, controlling the excess stomach acid, and any other symptoms that your cat may show. These will help in maintaining their quality of life.


Having a cat with kidney issues is not an easy thing for any pet parent. However, with the right diet, proper management, and early diagnosis, you can help your cat live longer and healthier. Following the points such as those that we discussed and consulting the veterinarian regularly will help make all of this more comfortable for you and your pet.