Kidney disease is a common ailment in cats as they age. When a cat’s kidneys are healthy, they work to manage blood pressure, stimulate the bone marrow to make more red blood cells, make hormones, and remove waste from the blood. As a cat ages though, the kidneys can become damaged, and all these processes can be harmed. While chronic kidney disease is a permanent condition that can’t be cured, there are thankfully treatments you can work with your vet on to slow the progression and keep your cat’s kidneys as healthy as possible for the rest of their life.
Types of kidney failure
There are two types of kidney failure in cats, and they each have different causes.
Acute renal failure
Acute renal failure is a sudden condition that happens over the course of days or weeks. It’s not something that just happens in older cats, it can happen in cats of all ages. The most common causes of acute renal failure are the following:
- Fluid loss. Blood loss, severe dehydration, extreme levels of activity, overheating, vomiting or diarrhea can all cause fluid loss that can lead to kidney damage.
- Trauma. Injury to the abdomen or pelvis can hurt the kidneys and cause failure.
- Kidney infection. This is why it’s so important for your cat to see a vet if you suspect a urinary tract infection. Untreated UTIs can easily lead to a kidney infection that has life-long consequences.
- Poisons. If your cat gets into cleaning supplies, poisons meant for pests, or something else, this can damage the kidneys.
- Blockages that would cause strain on the kidneys, such as a urethral blockage that would prevent a cat from urinating properly.
- Low blood pressure caused by heart failure.
While acute renal failure is scary, the good news is when caught soon enough the damage can be reversed. If you suspect any of these issues are happening with your cat, see a vet immediately.
Chronic kidney disease
Chronic kidney disease (CKD) is typically seen in cats aged 7 years and older. Chronic kidney disease usually happens more slowly and over a longer period of time than acute kidney failure. Sometimes there’s no known cause of chronic kidney disease, and no other medical issues will be found. In some cases, this form of kidney disease can be caused by the following issues:
- Kidney infection. Sometimes a less aggressive kidney infection, rather than causing acute kidney failure, will progress more slowly and the symptoms will be less noticable until its progressed into a chronic kidney failure.
- Blockage. Similar to kidney infections, blockages might progress more slowly and cause chronic kidney disease rather than accute.
- Advanced dental disease.
- High blood pressure.
- Thyroid problems.
Symptoms of kidney disease
Both forms of kidney failure have the same symptoms.
- Frequent urination. This is a sign that your cat’s kidneys can no longer hold onto water, and so their body is getting rid of it more quickly. The urine might also look cloudy.
- Drinking a lot of water.
- Loss of appetite.
- Weight loss.
- Ulcers in the mouth.
- A brown colored tongue.
- Breath that smells like ammonia or urine.
- Bacterial infections.
- Weakness and loss of interest in play or other things that normally interest your cat (watching birds, chasing the dog, etc).
How is kidney disease in cats diagnosed?
Kidney disease diagnosis is normally done with both blood and urine tests. Both of these will test how many waste products that the kidneys normally process are present in the urine and blood. Blood tests will be looking for the presence of blood urea nitrogen and creatinine. If these are present in high numbers, especially creatinine, that shows that your cat’s kidneys are not functioning as well as they should be. Since kidney failure isn’t the only reason those will be present in the blood (dehydration is another reason why those numbers could be high), typically two blood tests will be done about two weeks apart. One of those tests will be done under conditions where they’re sure the cat is hydrated and has fasted for at least 12 hours. These numbers will then be compared to each other to give an accurate diagnosis.
When testing your cat’s urine, the vet will also be looking for things that the kidneys should be filtering out, such as proteins, blood cells, bacteria and other waste. This test will also rule out urinary tract infections as the cause of your cat’s symptoms.
In some cases your vet might also want to do an ultrasound of the kidneys or a biopsy to get a more accurate diagnosis. Your cat’s blood pressure will likely be checked in addition to all of these tests, since high blood pressure can be a result of CKD.
What is the treatment for chronic kidney disease?
Unfortunately there is no cure for CKD, although there are treatments to slow the progression and avoid any complications that can be caused by CKD. The first thing will be to treat any underlying condition that has cause your cat’s CKD. For example, if your cat has a blockage, that will need to be resolved immediately.
Dietary changes will likely need to be made to keep your cat’s kidneys functioning as well as they can. Studies have shown that diets low in protein, phosphorus and sodium content can prolong the lives of cats with chronic kidney disease. You’ll also want to look for a food that’s high in water-soluble vitamins, fiber, and antioxidants. There are plenty of perscription foods your vet can provide. Felinecrf.org has a comprehensive list of quality foods and all their nutrient information if you’d like to find one that suits your cat and your budget. It can be dangerous for cats with CKD to go without food for too long, so make your transition to the new food slowly, and make sure your cat will eat what you give them.
If your cat has developed hypertension, an oral medication will be perscribed for that. To prevent protein loss in the urine, an ACE inhibitor medication might be perscribed as well. Anemia is another concern for cats with CKD, and if your cat has anemia erythropoietin replacement therapy might be something your vet will want to try. Erythropoietin is a hormone that is produced in the kidneys that produces red blood cells. Damaged kidneys might not produce erythropoietin as well, and therefore replacement erythropoietin will be given to keep red blood cell counts high. This is normally given in an injectable form that you will get from your vet and give to your cat several times a week.
Encouraging your cat to eat well and drink plenty of water will be very important. Give your cat quality foods that they will want to eat, and encouraging hydration by using a water fountain or mixing water in with their food are ways to keep your cat eating and drinking as they should.
There are additional treatments that your vet may suggest, but diet changes and treating the other conditions CKD might be causing are top priority.
With proper management of their condition, it’s possible your cat could live many more years without any additional complications from their disease. Prognosis really varies from cat to cat though. An otherwise healthy cat who recieves proper treatment can live a long, healthy life, although some cats do not respond well to any sort of treatment.