Feline Kidney Disease

Kidney disease is a common disease frequently seen in older cats above the age of 10yrs. Although it should be noted that it may also occur in young cats.

Kidney disease is a destructive process within the kidneys which can be caused by inherited defects, toxic substances, or infections.

The kidneys have several functions. They are responsible for the filtering of blood and the removal of waste substances from the blood stream. In addition to this they are responsible for producing urine and hormones which are involved in the production of new red blood cells.

Kidneys are comprised of many small functional units called nephrons. It is the nephron that is responsible for the filtering of wastes from the blood stream. It is these nephrons that become compromised or die as a result of kidney disease. As a result the ability of the kidneys to act as filters for the body becomes compromised and there is a build up of toxic waste substances that leads to your pet showing signs of kidney disease.

The signs of kidney disease are usually not seen untill approx 75% of the functional nephrons have been lost. These signs may include loss of appetite, increased thirst and increased urination, poor coat, vomiting, weight loss, lethargy and drooling due to mouth ulcers.

The first steps to diagnosing renal disease include obtaining a urine sample, and collecting a blood sample to assess the fuctional capacity of the kidneys. Other diagnostic procedures may include xrays, ultrasound and biopsy of the kidneys.

The treatment of kidney disease may require hospitalisation and intravenous fluid therapy to help remove waste substances from the body. During this time your veterinarian may repeat the urine test and blood test to monitor kidney function. Medications such as antibiotics and vitamin supplementation may also be administered.

Many animals with kidney disease require long term management by the owner, This will slow down the progression of kidney disease and allow the remaining nephrons to compensate for the loss of functional mass of the kidney. Dietary modification such as reducation in salts and minerals (phosphorous) and protein in the diet may help reduce the extra demands placed on the damaged kidney. There are currently several commercially designed diets availble such as Hills Science Diet K/D formulation. Subcutaneous fluids may ned to be given at regular intervals to ensure your pet is well hydrated. In addition to this clean fresh water should be available at all times.

Your pet may also be home on long term medication to help delay the progression of kidney disease. Such a medication is Fortekor (Benazepril). This drug dilates the blood vessels within the kidney allowing for greater blood flow and filtration of waste products within the blood stream. This drug will not cure or stop renal failure but it will delay end-stage renal failure.

Before we start Fortekor we recomend a Urine Creatinine protein ration to be done at the laboratory. This test is also one of the most sensitive for early kidney disease detection, often picking up changes well before blood levels are elevated.

If you have any further queries regarding feline kidney disease please do not hesitate to ask any of our veterinarians or arrange to make an appointment for your cat.

Dr Nicole Langsford edited Dr Bill Ryan 2008