Elevated Kidney Function in Dogs

The kidneys are a pair of vital organs that filter toxins out of the body; these toxins are a byproduct of normal metabolism. Once the body takes the nutrients that it needs form food, the waste, or toxins, are sent to the blood where they make their way to the kidneys to be filtered and removed by urine. If the kidneys are not functioning properly, these toxins build up in the blood and can cause your dog to become very ill.

The term kidney function refers to how efficiently the kidneys are functioning. Dogs with two healthy kidneys have 100 percent kidney function. A decline in kidney function of 30 to 40 percent is considered mild and your dog may not show any symptoms. Serious health problems will occur when the kidney function drops to 25 percent or less, and your dog will begin to show show signs of illness. Changes in blood values for certain toxins will appear if you take your dog into the vet for a blood panel test. It is at this point that your dog will be determined to have kidney disease. Kidney disease is the most common cause of death in older dogs.

There are two distinct types of kidney disease: acute and chronic.

Acute kidney disease occurs suddenly and is usually the result of your dog ingesting a toxin such as anti-freeze or rat poison, or a medical condition which alters the flow of blood to the kidneys such as dehydration, anemia, cardiovascular disease and even some drugs. Acute kidney disease can also be caused by trauma or an infection caused by an obstruction of the urine flowing out of the kidney.

Chronic kidney disease is a gradual, irreversible decline in kidney function. Chronic kidney disease can be caused by several different factors, which include poor diet, trauma, congenital defect or abnormalities, immune diseases, hypertension and toxins. Blockage of urine flow caused by bladder stones and kidney stones can also damage dogs kidneys. Many dogs will experience some degree of kidney disease due to the normal wear and tear of aging.

The symptoms for acute and chronic kidney disease will vary.

Acute kidney disease may cause the kidneys to completely shut down and your dog may be unable to produce urine. He will be dehydrated and may exhibit pain. He may appear disoriented and uncoordinated. It is important to seek veterinary attention immediately since acute renal failure may be treated and reversed. If you feel that your dog may have ingested anti-freeze or rat poison, do not wait for symptoms to appear. Take your dog to the veterinarian for immediate treatment, if you wait for symptoms to appear it will probably be too late.

Chronic kidney disease is difficult to diagnose early. The first sign you may notice is your dog drinking more water and urinating more. If you notice these signs and begin treatment early, it will go a long way in prolonging your dogs life. As the disease progresses, you will see your dog begin to lose weight, he will lose his appetite, develop bad breath, and experience nausea and vomiting. You may notice a discoloration of his teeth, muscle weakness and depression.

The diagnosis for both acute and chronic kidney disease are the same. Your veterinarian will perform a complete clinical exam and ask specific questions to determine the onset of the symptoms. He will perform several diagnostic tests including a CBC (complete blood count) to check for infection, and a blood serum panel to check the levels of BUN (blood urea nitrogen), creatinine and phosphorus By-products that will show high levels if kidney disease is present. He will perform a urinalysis to check for protein and blood in the urine and to check the specific gravity to determine if the kidneys are concentrating urine properly. In cases where there is suspected ingestion of anti-freeze, the veterinarian will look for crystals in the urine that are indicative of this situation.

Treatment for acute kidney disease is aimed at removing the cause and correcting life-threatening problems. Your dog will be given intravenous fluids to flush the kidneys, drugs to aid in the production of urine and electrolytes to correct abnormalities. Your veterinarian may induce vomiting to help remove the toxin. If it is determined that your dog has ingested anti-freeze he will be treated with 4-methylpyrazole (Antizol®) or ethanol intravenously.

Treatment for chronic kidney disease occurs in two phases and is aimed at flushing the kidneys and preventing additional damage. The first phase is to jump-start the kidneys by giving large quantities of intravenous fluids, this will aid in flushing the kidneys and enable the cells to begin functioning again. The second phase is aimed at preventing additional damage and keeping the kidneys functioning. Your veterinarian will prescribe a special low protein diet and a phosphate binder. Since protein and phosphate are filtered through the kidneys, this diet will decrease the workload on the kidneys. Your veterinarian may also teach you how to give sub-cutaneous fluids (fluids placed just under the skin) at home. These fluids, given on a regular basis, help to keep toxins from building up in your dogs blood and will make him feel better.

Acute kidney disease can be reversed if caught early; however, even with intensive treatment it is a very serious condition and is often fatal. It is imperative that you seek veterinary attention immediately if you suspect your dog has ingested anti-freeze.

There is no cure for chronic kidney disease. With the dietary changes and fluid therapies listed above, your dog may live several months or even years after diagnosis. It is up to you, the owner, to determine when the quality of your dogs life has deteriorated.