Chronic Renal Failure

Chronic renal failure (CRF) is the most common form of kidney disease in cats and dogs. It may have a genetic basis in some animals, but is commonly associated with the aging process. Normal kidneys perform several functions: filtering the blood to remove waste products from the body, concentrating the urine to conserve water, regulating mineral and electrolyte balance, and producing hormones to regulate various functions in the body. About 75% of the kidney tissue must be damaged before signs of illness appear.

Signs of CRF include:

increased thirst
increased urination
decreased appetite
weight loss
vomiting
diarrhea
bad breath
depression

These clinical signs are not specific for CRF, so your veterinarian may suggest that bloodwork and urinalysis be performed to help pinpoint your pet's condition. If your pet does have CRF, he/she may have all or some of the following changes:

increased blood urea nitrogen (BUN) levels
increased blood creatinine levels
increased blood phosphorus levels
anemia (low numbers of red blood cells)
decreased urine specific gravity (poor urine concentrating ability of the kidneys)

Although CRF is not curable, it can often be effectively managed to help your pet feel better, live longer, and lead a higher quality of life. Treatment may involve all or some of the following issues:

In early CRF, the first step is to change your pet's diet to a kidney-protecting diet, a diet lower in protein. However, if your pet refuses to eat the special diet, it is important that they continue to eat something. This is especially true for cats.

As the kidney failure progresses, owners can be taught to give subcutaneous fluids at home. Keeping your pet hydrated is the single most important treatment you can provide.
In cases where there are severe changes in the pet's health and/or bloodwork, intravenous fluids given in the hospital may be needed to help flush waste products from the pet's body and improve hydration. Once the pet is stable, home treatment can be provided by the owners.
Animals that have high blood phosphorus levels may require oral phosphate binders (such as aluminum hydroxide) to help reduce the amount of phosphorus absorbed by the intestine.
The waste products accumulating in the bloodstream may cause ulcers in the mouth and stomach. Histamine H2-receptor blockers, such as Pepcid AC, can be helpful.
Pets that are anemic may require treatment to stimulate the bone marrow to produce more red blood cells. Agents used for this purpose include Winstrol (a steroid) and Epogen (a synthetic renal hormone).

Occasionally, animals may have low blood potassium levels and may require oral potassium supplementation.
Some universities are currently performing kidney transplants. This procedure is very delicate and costly. If you are interested in this procedure, ask your veterinarian about contacting your local veterinary college.

Once your pet is stabilized, it is important to monitor their kidney function closely by checking their hydration status (your veterinarian can teach you ways to check this) and repeating bloodwork and/or urinalysis as needed.

Please contact your veterinarian if:

there is a change is your pet's water intake and/or urinations
your pet is reluctant to eat or seems depressed
your pet vomits or has diarrhea
your pet faints or acts dazed or confused