• Join our Facebook Page!
  • Follow us on Twitter!
  • Subscribe to our YouTube channel!
  • Subscribe to the Wiki-Pet.com RSS feed
  • |

208 Breeds, 422 Health Conditions  |  Find a Vet

Wiki Pet - health, breeds, pets, friends!

Kidney Failure (Uremia)

Advertisement

Advertisement

Advertisement

Condition Overview

Kidney failure is defined as the inability of the kidneys to remove waste products from the blood. The buildup of toxins produces the signs and symptoms of uremic poisoning. Kidney failure can appear suddenly (acute kidney failure) or come on gradually over months.

Symptoms

One of the first things you may notice is that your dog drinks and urinates more than usual and indicates her need to go outside to eliminate sever times a day. If not allowed to do so, the dog may begin to have accidents in the house. These signs are due to the failure of the kidneys to concentrate the urine. This results in a large urine output over which the dog has no control, with subsequent dehydration and thirst.

As kidney function declines, the dog retains ammonia, nitrogen, acids and other chemical wastes in her blood and tissues. This is called uremia. The degree of uremia is determined by measuring serum blood urea nitrogen (BUN), creatinine, and electrolytes.

Signs of uremia are apathy and depression, loss of appetite and weight, a dry hair coat, a brownish discoloration to the surface of the tongue, and an ammonia-like odor to the breath. Dogs at this stage may urinate less than normal. Ulcers may arise in the mouth. With the nephrotic syndrome, the dog develops ascites (for an accumulation of fluid in the peritoneal cavity) and edema. Vomiting, diarrhea, and gastrointestinal bleeding may occur. At the end stages of kidney failure, the dog falls into a coma.

A condition called rubber jaw may be seen with chronic kidney failure. It is characterized by loosening of the teeth and ulcerations of the mouth and gums. This can also occur with a diet low in calcium or an imbalance of calcium and phosphorus.

Causes

Causes of acute kidney failure include:

  • Complete urinary tract obstruction caused by a stone
  • Rupture of the bladder or urethra
  • Shock, with inadequate blood flow to the kidneys
  • Congestive heart failure with low blood pressure and reduced blood flow to the kidneys.
  • Poisoning, especially from antifreeze
  • Lyme Disease
  • Leptospirosis
Dogs with kidney failure do not show signs of uremia until 75% of functioning kidney tissue is destroyed. Thus, a considerable amount of damage occurs before the signs are noticed.

Diagnosis

Your veterinarian may wish to make an exact diagnosis by performing exploratory surgery and biopsy of the kidney, or doing an ultrasound-guided biopsy. This helps to guide treatment and determine whether the disease is treatable.

Treatment

Dogs with kidney failure require periodic monitoring of blood chemistries to detect changes in kidney function that may require medical intervention. A most important step is to restrict salt intake. This helps prevent edema, ascites, and hypertension.

Protein is poorly metabolized by dogs with kidney failure, but the solution to diet protein levels is currently an area of controversy. Some veterinarians believe a diet rich in meat, or one that contains poor-quality protein, creates an increased nitrogen load that must be handled by the liver and kidneys. Dogs with weak kidneys can be thrown into uremia by feeding them more protein than they can handle. Other veterinarians believe that as long as the protein is of high biological value, it will help the kidneys retain their function. Diet may need to be customized to the individual dog.

Restricting phosphorus intake is agreed upon by all. Medications to lower phosphorus levels may be required along with dietary adjustments.

While there are prescription diets available from your veterinarian, it is recommended that you seek premium brand alternatives. These alternatives (offered from brands like Innova) provide a higher quality ingredient list while retaining the requirements set forth in the prescription foods.

It is extremely important to provide fresh water at all times. The dog must be able to take in enough water to compensate for the large urine output. Some dogs will need an occasional boost to their fluid intake. This can be done by giving subcutaneous (known as sub-Q or SQ) fluids. With most dogs, their owners can learn how to do this from home. In the later stages of kidney failure, dogs may need sub-Q fluids daily.

B vitamins are lost in the urine of uremic dogs. These losses should be replaced by giving vitamin B supplements. Sodium bicarbonate tablets may be prescribed by your veterinarian to correct an acid-base imbalance. A phosphorus binder, such as Amphogel, may be recommended to lower the serum phosphorus.

A dog who becomes dehydrated because of illness or failure to drink enough water may decompensate suddenly, a condition called a uremic crisis. The dog should be hospitalized and rehydrated with intravenous fluids and balanced electrolyte solutions.

Some types of kidney failure are actue, and are mild enough that if the dog is well supported medically, there will be a complete recovery. More commonly, dogs will have at least some renal (kidney) function deficit and need a change in care for the rest of their lives. With chronic renal failure, there is no cure. The disease must be controlled as well as possible for the rest of the dogs life.

Dialysis

Dialysis describes two therapies that try to duplicate the filtering tasks of the kidneys. In peritoneal dialysis, special fluid is put into the abdomen using a catheter. The fluid then washes tissues and absorbs toxins from the body across tissue barriers. After a set period of time, the fluid is removed through the same catheter, taking the toxins with it. This technique has been used in veterinary referral centers for short term kidney problems such as antifreeze poisonings.

Hemodialysis is the second technique. This therapy is only available at a few referral centers across the country, because the equipment is expensive and must be specifically designed to work with dogs. The dog's blood is circulated through a machine with filters that tries to duplicate the filtering tasks of a healthy kidney. Special catheters are required and dogs need treatments of 3 - 4 hours, up to 3x per week. This is a very expensive therapy and is ideally only needed for short-term problems such as poisoning or leptospirosis - giving the dog's own kidneys time to heal.

Dogs with chronic kidney failure have ben maintained on hemodialysis for up to one year (this is not common).

Kidney Transplant

Another option for dogs with terminal kidney failure is to consider a kidney transplant. Kidney transplants are only done at a few veterinary referral centers, but are becoming more common.

As with human transplant patients, drugs must be given post-transplant to prevent organ rejection. These drugs are quite expensive and must be carefully calibrated to minimize side effects.

The current method for finding kidney donors is to test shelter dogs for tissue compatibility. The shelter dog then donates one kidney - dogs, like people, can survive with just one healthy kidney. The shelter dog is then adopted by the family of the recipient dog, who have to agree ahead of time to provide a home for the donor dog for the rest of their life [citation needed].

Prevention

Information needed.

Support

Please contact your veterinarian with questions regarding this condition.

Show Sources & Contributors +

Sources

Dog Owners Home Veterinary Handbook

Publisher: Wiley Publishing, 2007

Website: http://www.wiley.com/WileyCDA/

Authors: Debra M. Eldredge, Liisa D. Carlson, Delbert G. Carlson, James M. Giffen MD

0 Comments For "Kidney Failure"