Kidney problems are one of most common disorders veterinarians see in older cats. While no one knows the exact cause, researchers are hard at work trying to figure out what causes cat kidney health to fail in aging pets. Genetics, decreased thirst drive, undiagnosed chronic kidney infections, hyperthyroidism, dental disease and high blood pressure are all thought to contribute to chronic kidney problems in cats.
Even though cats can develop acute (sudden) kidney failure, kidney stones, cancer and infections in their kidneys, chronic kidney insufficiency is the most common condition seen in cats. If your cat is 7 years old or older, then it is important that you know the health of her kidneys.

Why Kidneys Are Important
When it comes down to it, kidneys are awesome, versatile, bean-shaped little organs. Kidneys filter the blood, creating urine to remove excessive levels of water, minerals, waste and toxins from the blood. Their filtration maintains proper electrolyte balance in the body.
Kidneys also make several types of hormones that benefit several systems in the body. These include hormones that regulate blood pressure, stimulate the bone marrow to make red blood cells and promote the absorption of calcium from the intestines. If a person or a cat develops kidney disease severe enough to decrease the kidneys' ability to function, the whole body suffers.
Signs of Kidney Disease in Cats
Cat kidney symptoms are classic, meaning all cats with decreased kidney function generally show the same signs. The earliest sign of kidney problems in cats is increased thirst and urination. Damaged kidneys are not able to process water, and so the cat pees more, which makes her thirsty, so she drinks more, and then pees more ... and so on and so forth. Keep track of how often your cat goes to the litter box on an average day so you can spot a problem quickly if one arises.
Another classic sign of kidney disease is weight loss and decreased appetite. The reason for this is that ailing kidneys lose the ability to filter toxins from the blood, and this makes the cat feel sick and nauseated. Other classic cat kidney signs include:
- Vomiting
- Decreased grooming
- Increased blood pressure
- Painful mouth ulcers that contribute to appetite loss
Another sign of poor cat kidney health is the acute onset of blindness and dilated pupils. Since kidneys help regulate blood pressure, if they are damaged, high blood pressure can lead to detachment of the retina in the back of the eye, leading to irreversible blindness.