What is Chronic Kidney Disease in Cats?

Introduction

When Sarah noticed her Siamese cat, Whiskers, displaying unusual symptoms like increased thirst, weight loss, and poor coat condition, she became increasingly worried about her feline friend’s health. Seeking answers, she brought Whiskers to the veterinarian for a thorough examination. After running several tests, the veterinarian diagnosed Whiskers with chronic kidney disease, a common and progressive illness in cats.

Kidneys filter waste products from the blood and produce urine. They also help regulate body temperature, maintain fluid balance, and control blood pressure. In addition, the kidneys work together with the liver and pancreas to remove toxins from the body.

If the kidneys fail to function correctly, wastes accumulate in the bloodstream, and fluids become too concentrated. This condition is called chronic kidney disease in cats. CKD causes serious health problems, including heart failure, stroke, and death.

There are many different types of CKD. Some cause no clinical signs until the advanced stages. Others may be diagnosed early when there are only mild signs or symptoms.

There are two types of kidney failure: acute and chronic. Acute CKD develops rapidly and is often fatal. Chronic CKD takes longer to progress and is generally much milder.

• Acute kidney failure is a sudden loss of renal function, usually when critical kidney damage occurs. AKI is any condition characterized by rapid deterioration of kidney function resulting in increased creatinine levels in blood and urine. The most common causes of AKI include sepsis, shock, trauma, certain medications, and dehydration. It is estimated that around 1 million people develop AKI yearly in the United States alone.

The term “acute” refers to the short duration of the illness. In contrast, chronic kidney disease (CKD) is a long-term disorder of the kidneys. CKD is diagnosed when the glomerular filtration rate (GFR), which measures how well your kidneys filter waste from your blood, falls below 60 ml per minute. This means that you have less than 60% of normal kidney function.

• Chronic Kidney Failure is a condition where your cat’s kidneys don’t work correctly. It happens when your cat has problems filtering waste products from your blood. Waste products include extra fluid, protein, and potassium. Your cat’s body doesn’t get rid of these wastes fast enough, so they build up inside the body. This buildup causes damage to your cat’s organs and tissues. Over time this damage can lead to serious health problems such as heart failure, stroke, and even death.

Causes of Chronic Kidney Disease in Cats

Cats develop chronic kidney disease (CKD) when their kidneys fail to filter waste properly out of their blood. This leads to the accumulation of toxins and fluid in the body. Veterinarians have estimated that 20%-50% of older cats may have some form of chronic kidney disease (CKD).

There are many reasons why cats develop CKD. Some common ones include:

1. Cats’ most common cause of chronic kidney disease (CKD) is obesity. Obese cats may be prone to diabetes, hypertension, and heart problems. They also risk developing CKD because they eat too many calories.
2. Another major factor contributing to CKD in cats isdiabetes mellitus. Diabetic cats often develop hyperglycemia, which leads to excessive urination and dehydration. Over time, this may lead to damage to the kidneys.
3. High dietary sodium intake contributes to CKD in cats. Sodium is found naturally in table salt, processed foods, and canned cat foods. However, many commercial pet foods contain far too much sodium. Too much sodium can lead to water retention and hypertension.
4. Consider switching brands if you feed your cat a diet containing excess sodium. Look for a brand with no added sodium and only fresh, whole foods for your cat.
5. Another factor that causes chronic kidney disease (CKD) in cats is hypercholesterolemia. Hypercholesterolemia occurs when there is too much cholesterol circulating roughly in the blood. This excess cholesterol causes damage to the kidneys and eventually leads to CKD.
6. High-cholesterol diets are associated with CKD in cats. However, not every cat fed a diet rich in cholesterol develops CKD. Some cats develop CKD because of genetic factors. Infection may be another factor, too. 

Symptoms of Feline Kidney Failure

Cats with chronic kidney disease (CKD) usually show symptoms early in life. These include vomiting, diarrhea, weight loss due to poor appetite, lethargy, and depression. The most common clinical sign is vomiting. Cats may repeatedly vomit throughout the day. They may also vomit blood.

Other signs include lack of appetite, weakness, and dehydration. Some cats develop kidney failure, which leads to death.

Diagnosis of Chronic Kidney Disease in Cats

If your cat shows any of these symptoms, he should be checked out by his veterinarian. The vet will perform blood tests to determine any underlying cause for the problem.

Blood Testing

This is the most reliable and accurate way to diagnose Chronic Kidney Disease. The American Society of Veterinary Clinical Pathology recommends performing a complete blood count (CBC), serum biochemistry panel, urinalysis, and urine protein/creatinine ratio (UPC).

Your vet will use a needle to draw blood from your cat’s vein to perform these tests. Blood samples will be sent to a laboratory where technicians analyze them. Results usually take several days to return.

Once the results return, your vet will review them with you and discuss any treatment options.

Your vet may recommend additional testing, including urine analysis, x-rays, ultrasound, and biopsy.

Urine Analysis

The urine test is a simple test used to diagnose cat kidney disease. The test involves collecting urine samples from your cat and analyzing them for protein content and specific gravity. This information helps determine whether your cat has any kidney disease.

X-ray Imaging

It is a standard diagnostic tool used to detect diseases in animals. X-rays pass through body tissues and allow doctors to view internal structures.

Cats are no different than dogs when it comes to diagnosing kidney problems. They both require blood tests and urinalysis to determine whether there is any kidney damage.

However, cats’ kidneys are not visible during an ultrasound exam. Therefore, veterinarians use radiographs (x-rays) to examine them.

When performing a radiograph, the cat must be sedated. This allows the veterinarian to place the cat inside a machine that exposes the animal to radiation. The machine takes pictures of the cat’s organs, including its kidneys.

Ultrasound Technology

This is widely used to detect kidney problems in dogs and cats. Ultrasounds use sound waves to create pictures of internal organs. The technique is safe and painless, and there are no side effects.

However, ultrasounds aren’t perfect at detecting small tumors, cysts, and stones. So, when ultrasonography fails to reveal abnormalities, veterinarians may resort to other diagnostic tests, including blood work and urinalysis.

Biopsy

A biopsy is a medical procedure where tissue samples are removed from a patient for examination. Biopsies are commonly performed to determine whether cancerous cells exist within the body.

To confirm a diagnosis of CKD, veterinarians perform a renal biopsy, which involves removing a small piece of tissue from the cat’s kidney. This sample is examined under a microscope to detect signs of inflammation, infection, or neoplasia.

Treatment for Chronic Kidney Disease in Cats

Treatment for CKD depends on the cause. Treatment may involve medications, dietary changes, surgery, dialysis, or transplantation.

• Dietary Changes

Cats with CKD often have problems regulating their water balance. As a result, they drink too much and urinate frequently. To prevent dehydration, your cat should be fed a diet low in protein and sodium.

A commercial food formulated specifically for cats with CKD is available. Be sure to feed this diet for several days before beginning any treatment.

• Medications

Medication is used to treat certain conditions associated with CKD. These include anti-inflammatory drugs, diuretics, antibiotics, and analgesics.

Anti-inflammatories are used to control pain and inflammation caused by CKD. Diuretics are prescribed to decrease urine output and prevent further accumulation of fluids in the body. Antibiotics are given to kill bacteria that may cause infections. Analgesics are used to relieve discomfort.

• Dialysis

Dialysis is used to replace lost fluids and nutrients in the blood. It involves removing toxic materials from your cat’s blood using a hemodialyzer filter.

This procedure requires frequent visits to the veterinarian.

• Surgery

Surgery is sometimes necessary to correct complications resulting from CKD. For example, surgical blockage removal may be required if your cat has developed urethral obstruction due to bladder swelling.

Other surgeries may correct spine, hips, knees, or feet abnormalities.

Prevention and Management of Kidney Diseases in Cats

There are several ways to prevent kidney disease in cats.

• Limit your cat’s intake of red meats. Red meat causes kidney disease in cats. This is because the kidneys filter blood from toxins and waste products.

When there is too much protein in your cat’s diet, this extra protein can damage their kidneys. This damage can lead to chronic kidney failure.

• Feed your cat a diet rich in antioxidants, including green vegetables, fruits, whole grains, and omega-3 fatty acids. A diet rich in antioxidants helps cats with kidney disease because they contain many essential nutrients for our health.

Antioxidants are molecules that protect cells from damage caused by free radicals. Free radicals are unstable atoms or molecules that cause cell damage when they react with everyday body chemicals.

They are produced naturally during metabolism, and in some cases, such as exposure to radiation, tobacco smoke, pollution, or certain medications, they can increase in numbers.

• You protect your cat from toxins, such as cleaning chemicals, household cleaners, and pesticides. However, toxins can accumulate in your cat’s system over time.

If you notice your cat licking himself excessively, vomiting, or having diarrhea, contact your vet immediately.

• Give your cat plenty of exercises, especially during warm weather when he needs to cool down. Exercise helps his body eliminate toxins through urination. 
• Make sure they get enough water. Cats should drink at least 1 cup (24 ounces) of water daily. Contact your veterinarian immediately if you notice any changes in their behavior, such as drinking less than usual, vomiting, or losing weight. 
• Avoid giving your cat foods containing high levels of phosphorus. Phosphorus is an essential mineral in your cat’s body’s bones, teeth, and other parts. Too much phosphorus can build up in your cat’s bloodstream and cause kidney stones.

Phosphorous also contributes to calcium buildup in soft tissues, which can result in bone spurs on your cat’s joints.

• Be aware of signs of kidney disease in your cat. These include vomiting, diarrhea, lethargy, weight loss, excessive drinking, and urination outside the litter box. If you notice any of these symptoms, contact your veterinarian right away.

Frequently Asked Questions