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Renal Failure
Veterinary Extension
2938 Vet. Med. Basic Sciences Bldg.
2001 S. Lincoln Ave.
Urbana, Illinois 61802
Phone: 217/333-2907
By Joseph Hahn
Information Specialist
University of Illinois
College of Veterinary Medicine
What purpose do kidneys serve? Your pet's kidneys clear the blood of toxins and conserve water at times when an animal isn't drinking as much as it should. When the kidneys deteriorate (chronic renal failure), it can lead to serious health problems for your pet.
"Chronic renal failure is a slow deterioration of the kidneys resulting from a variety of inherited or acquired disorders," says Dr. Donald Krawiec, a veterinarian specializing in urology and chief of small animal medicine at the University of Illinois Veterinary Medicine Teaching Hospital at Urbana. "It occurs in middle-aged to older cats and dogs."
He explains that "the signs are so vague that they could mimic almost any other condition." These signs include excessive drinking or urination, weight loss, loss of appetite, vomiting, or general signs of not feeling well.
"There is still a lot we don't know about chronic renal failure," remarked Dr. Krawiec. "Most of the toxins that are cleared from the blood by the kidney tend to be products of protein metabolism. Therefore, we reduce the amount of protein in the diet to help alleviate this problem. We also know that animals in renal failure have a hard time regulating phosphorus and that plays a role in the progression of the disease. Finally, we know that in humans hypertension (high blood pressure) plays a role in the disease so in animals we tend to reduce salt in the diet as well."
The main treatment for renal failure is dietary. Protein, phosphorous and salt are reduced in the diet to help slow the progression of the disease. Your veterinarian can recommend an appropriate diet, most of which are commercially produced and readily available. The diet is also supplemented with water soluble vitamins. If necessary, the animal is treated for anemia if the condition is present.
Renal failure is usually first diagnosed with a blood test and urine sample and later with the help of radiography. Monitoring for mild renal failure is not rigorous. At first, animals will need to be seen monthly until the rate of the renal failure is determined. Once this is determined, most animals require only once- or twice-a-year visits.
"The progression of this disease is highly variable," explains Dr. Krawiec. "Renal failure will progress rapidly in some animals and slowly in others. Cats will tend to progress more slowly than dogs."
"As with people, the cause with chronic renal failure in dogs and cats is currently unknown," he says. "It is important to be observant with your dog and communicate any unusual changes or behaviors with your veterinarian. The changes may be subtle but it helps if it can be identified before the animal is overtly ill."
If you would like further information on chronic renal failure, contact your local veterinarian.
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