Chronic renal failure, or kidney disease in cats, is a very common condition in cats. This is especially the case in older cats. Often chronic renal failure will advance over time so that there is a gradual worsening of the cat disease. Treatment of the disease and support can benefit the quality of life and longevity of life by reducing the evolution of the sickness.
Renal Failure Cause? Chronic renal failure or kidney failure occurs when there has been progressive and permanent damage to the kidneys that reduces their capacity to filter and remove waste from the blood. Often when kidney disease is diagnosed, the precise origin of the disease is unknown. Kidney samples taken from cats often show considerable amounts of fibrous tissue replacing the normal kidney tissue, thereby reducing the productive kidney tissue over time.
Signs, Symptoms & Diagnosis of Kidney Disease Kidney Disease has the potential of affecting any cat, but is often seen in older cats. The older the cat the more frequent the disease will become. It has been estimated that around one in five cats over 15 years of age has renal failure. Unfortunately for cats, kidney disease is 3 times more common for them than for dogs.
Some of the important functions that the kidney provide including removing toxins from the blood and maintaining water and salt balance in the body. Blood is constantly filtered through the kidneys to remove the toxic waste that body functions produce. A byproduct that is produced in this process is urine. The kidneys also concentrate the urine by returning water to the body, preventing dehydration.
In most cases chronic renal failure is a progressive disease with a deliberate, menacing onset, although occasionally the signs may appear to develop very quickly. Some signs of kidney disease are quite vague - caused in part simply from the accumulation of toxins in the blood that would normally be extracted by the healthy kidneys. The most common signs seen in affected cats are a poor appetite, weight loss, dehydration, lethargy and depression. There is often an increased thirst along with increased volumes of urine being produced (due to an inability to concentrate the urine in many affected cats). Other signs may include a poor coat, vomiting, bad-smelling breath, ulceration in the mouth and weakness. These symptoms will become worse over time.
As signs can be vague diagnosis of kidney disease is therefore made by collection of blood and urine samples. Urea and creatinine, two substances in the blood – are commonly analysed, as these are products of metabolism that are normally excreted by the kidneys. In renal failure the blood concentration of these two products will be increased.
Diet Is Important Dietary management is important for cats with chronic renal failure, and there are three main aspects to this:
Water intake
Cats with kidney disease are more likely to become dehydrated (due to the reduced ability of the kidneys to conserve water by concentrating urine). Maintaining a good fluid intake is very important, and as cats generally gain much of their water from their food, whenever possible, cats with chronic renal failure should be moist foods rather than dry foods.
Protein content
Some promote an ideal diet for a cat with renal failure being a low protein content – many of the toxic products that accumulate in the blood in renal failure are a result of protein breakdown, and feeding a low protein diet will therefore help to minimize this. However, protein restriction has to be performed with care. Too little protein in the diet can lead to excessive weight loss that would be extremely detrimental to general health. And some authorities disagree with these procedures. We advise you to speak to your vet before implementing any dietary plan.
Low phosphate content
One way to help protect the kindneys from further damage is to restrict the phosphate content in the diet of the cat. Often cat food designed to help cats with kidney disease have low levels of both protein and phosphates.
The prognosis for cats with renal insufficiency depends on the degree of damage the kidneys have or more importantly, the degree of function they still have left. Fluid therapy and drug therapy can allow cats to leave relatively happy lives for months to a couple of years. Cats that can not be stabilized for home management carry a worse prognosis and euthanasia should be considered. Unfortunately, if a cat lives long enough it will likely have some degree of renal insufficiency. Regular veterinary exams and blood work in older cats may allow us to detect these patients early and keep them happy and comfortable for longer. Other disease that may make renal failure worse are hyperthyroidism, and hypertension.