Kidney or Renal Disease is a common problem in cats, especially as they age. In fact, more than half of cats over 15 years old are affected by some form of renal disease. Some breeds (Persians, Himalayans and British Shorthairs) may be predisposed to kidney problems, however, any cat can develop renal failure if there has been enough damage to these important organs. Unfortunately, as a species, cats seem to be particularly susceptible to kidney damage, and in the veterinary field it’s common knowledge that renal issues are a big problem in our senior felines.
What do kidneys actually do?
Kidneys are involved in getting rid of waste and by-products from metabolic processes in the rest of the body. They help regulate blood pressure and balance water and electrolytes in the blood stream. They produce hormones and enzymes and are important for red blood cell production.
Normal kidneys filter the blood through very small and clever little filtration units called nephrons. As blood enters the kidneys it’s forced through these little units which remove waste products, precisely balance water and salt content and then send the ‘clean’ blood back to the heart to send around the rest of the body again. The waste products, excess water and salts are excreted as urine which passes down the ureters and into the bladder to be excreted at a suitable time.
Kidneys have a fantastic reserve capacity i.e. they have nephrons in excess to that which is actually required by the body. In fact, it’s only once 75% of the kidney tissues are damaged that we will actually start to see clinical signs of illness. Unfortunately, by the stage we see those signs, the kidney cells have been severely damaged, have died off and then there is no way to get them to heal or regenerate.
What are the clinical signs of kidney disease?
Because kidneys have a huge reserve, we very often won’t have any early warning signs that there is a problem brewing. Later on, when a pet is more affected we may see:
- Increased thirst
- Increased urination
- Weight loss
- Decreased appetite
- Listlessness and lethargy
- Vomiting and nausea (licking the lips)
- ‘Tenting’ skin because of dehydration
How is kidney disease diagnosed?
Owners discussing their pet’s drinking or urination habits, often give the attending vet clues that a kidney issue may be developing, so please talk to your vet about the amount your cat has been drinking or urinating if there has been a change – we won’t think that you’re strange because you’re keeping tabs on their trips to the loo!
If kidney disease is suspected, urine and blood tests will give information as to how well the kidneys are able to concentrate the urine, whether there is an accumulation of waste-products in the blood and whether there may be an infection causing the kidney damage. Further tests like X-rays, ultrasound, urine culture or kidney biopsy may be necessary to determine a cause.
How is kidney disease treated?
Treatment is aimed at the cause of the disease. Acute (sudden onset) disease is often an emergency and requires intensive supportive care to help the body get rid of toxins and maintain fluid and electrolyte balance whilst trying to prevent damage to more kidney cells.
Chronic (slow and progressive) kidney disease treatments are aimed at slowing down the damage. This means identifying an underlying cause, where possible, and treating for that condition. Unfortunately, because of the slow progression of this disease it can be quite difficult to find a specific cause as there are many changes over many years which can cause chronic kidney damage. High blood pressure and urinary protein leakage are complications of kidney disease but can also lead to more damage to the remaining cells, so they need to be treated where possible.
A special diet consisting of a reduced quantity of high quality protein, suitable energy (from non-protein sources), restricted phosphorus and appropriate levels of vitamins, minerals and Omega 3 fatty acids assist cats in living longer with fewer episodes of severe illness associated with renal disease. There are several prescription diets to choose from now which makes managing these cats a little easier.
Other supportive care may involve re-hydration with subcutaneous fluids, nutritional supplements and medications to stimulate appetite and reduce nausea or managing other complications associated with kidney disease.
What causes kidney disease and can it be prevented or cured?
Acute kidney disease can be caused by cats ingesting toxins such as antifreeze, pesticides, lilies or other plants, cleaning fluids, human medications such as ibuprofen OR by blockages which prevent the flow of blood to the kidneys or flow of urine away from the kidneys. If this is caught early and treatment started quickly, these pets have a fighting chance.
Chronic disease cannot be cured. It usually takes many months or years to develop and usually affects cats older than 7 years. Regular blood and urine tests assist in detecting changes as early as possible. It’s sometimes difficult to decipher the exact cause of chronic kidney disease but clear links between dental disease, kidney infections, chronic inflammation elsewhere in the body and urinary tract obstructions have now been established. This means that if these conditions are addressed and managed, their impact on the kidney health can be reduced and so reduce the chances of developing chronic renal failure.
Speaking to your vet is an important part of helping your cat get early care. If you are concerned about your kitty, especially if he or she has been drinking more or going to the toilet more, these may be the first signs of kidney issues. Please give us a ring on 0481 527 678 or email to book an appointment to get him or her checked out.