Kidney Disease in Cats

It is estimated that 30 percent of middle-aged cats develop kidney disease, while over 50 percent of senior cats do. It is the number one health problem found in older cats. Generally, the disease is chronic and degenerative, although in the case of acute kidney disease from injury, recovery is possible. Kidneys that have lost function begin to allow toxic waste to flow back into the bloodstream. This can be devastating to other organs. Veterinary treatment can greatly improve the overall quality of life for a cat with kidney disease.

As most cats age, the kidneys weaken and become less effective at producing concentrated urine. To compensate for this, the kidneys produce copious amounts of urine in an attempt to eliminate waste from the blood stream. In addition to removing fluid waste, the aid in regulating chemicals within the bloodstream, keeping blood pressure at appropriate levels, and producing hormones and enzymes for the body. Weakened kidneys slowly become overwhelmed with all of these normal processes, and the entire body starts to suffer.

Professional care should be sought upon the first symptom arising. The more symptoms that are present, the more dire the situation is for the cat. Symptoms are listed below:

• Decreased appetite
• Weight loss
• Vomiting
• Polydipsia (increased thirst)
• Polyuria (frequent urination)
• Urination in unusual spots (outside litter box)
• Lethargy
• Depression
• Mouth ulcers
• Halitosis (bad breath)
• Pale gums
• Anemia
• Dull hair coat
• Itchy skin
• Low body temperature
• Weakness
• Sudden blindness (in extreme cases) 

Cats are especially susceptible to kidney disease. Their kidneys tend to weaken easily, and have a difficult time recovering. Known causes are include:

• Genetic predisposition (as seen in Persian, Himalayan and British Shorthair cat breeds)
• Birth defects
• Traumatic injury to the kidney
• Blockages in the bloodstream or urinary tract
• Dental disease
• Ingestion of toxic substances (including pesticides, cleaners or antifreeze)
• Kidney infections
• Obesity

The earlier that kidney disease is diagnosed, the better outcome for the cat. Once at the veterinary clinic, the vet will require your cat’s extensive medical history. Blood work will be needed. A biochemical panel will be taken from the blood work to measure the waste build up along with other compounds in the blood. If excessive amounts of creatine are found, this indicates that the kidneys are no longer filtering properly. Unfortunately, this test can only detect disease after the kidneys have lost 75 percent of their functionality. 

Another blood test will be conducted to check for symmetric dimethylarginine (SDMA) which is a waste produced by protein. This type of blood test can detect disease up to 9 months earlier than a biochemical panel. Urinalysis will be taken to examine the physical, chemical and microscopic details of the urine. This will also identify bacteria if any infections are present. X-rays or ultrasounds, along with biopsy, may also be required depending on the extent of damage from the disease. 

The best treatment option is very dependent on the disorder present (chronic or acute) and the progression of the disease. 

Acute Kidney Disease

This is generally a medical emergency. Injury or other sudden onset of kidney disease must be treated aggressively. Any possible medication that could be exacerbating the kidney failure must be stopped. If blockages are present, removal (sometimes surgically) is vital. An IV solution will be infused into the cat to rehydrate and correct fluids. Dialysis may be used to help the cat return to stable kidney function. In some instances, damage can be reversed. 

Chronic Kidney Disease

A key to treating CKD successfully is to identify the underlying cause of its presence. An early diagnosis usually gives the cat a better life expectancy. Medication will be prescribed to slow the progression of the disease. High blood pressure medication may also be prescribed. Proteinuria (high amounts of protein in the urine) can be managed. A diet plan including limited amounts of high quality protein, vitamins B, and C and rich in omega 3 fatty acids has been proven to lengthen life for the affected cat. At-home fluid therapy may also be required. 

Renal Transplant 

In either type of kidney disease, renal transplant may be possible if your cat is in stable enough condition to undergo the surgery. Only select universities and hospitals will perform this surgery. It is extremely expensive and may not increase the lifespan of the cat. Immunosuppressive drugs will be needed for the rest of the cat’s life. 

Surgical Removal 

If only one kidney is affected, and the other is in great condition and able to handle an increase in production, surgical removal of the diseased kidney may be an option. It is a high-risk surgery, but can potentially alleviate kidney problems for some time.  

Palliative Care

If the kidney disease has progressed too far, palliative treatment may be the only option. The cat will be given hydration support and assigned a therapeutic diet to ease stress on the body. Nausea can be medically reduced and appetite stimulated. All secondary issues may be treated to ensure the cat’s overall comfort. 

In cats suffering from acute kidney disease, if treatment is survived the prognosis is generally good. For cats suffering from chronic kidney disease, life-long treatments of medications and regular evaluation will be needed. Water should be kept fresh to encourage the cat to drink regularly. Proper diet can add years to a cat with CKD. Food may need to be warmed to entice the cat. Antioxidants may contribute greatly to the internal battle of CKD. Unfortunately, as there is no cure for this disease, euthanasia will eventually be required. 

If your cat has undergone surgery, strict at-home care must be adhered to. All incisions should be kept clean and monitored for the development of infection. If any signs are present, immediately bring your cat back to the veterinarian. Lower all possible causes of stress within your home. If your cat has undergone a renal transplant, this usually requires the adoption of a young, healthy, shelter cat (who is used as the kidney donor). Make adjustments in your home to accommodate this new cat while not infringing on your original cat’s healing process.