Kidney Failure and Excess Urea in the Urine in Dogs

The kidneys are essential to your dog’s health, just as your own kidneys are to your health. Kidneys remove the metabolic waste and produce urine to flush the waste out of your dog’s body. The blood flowing through the kidneys is filtered so the body knows how much water your dog’s body needs to keep in the blood and how much to get rid of. There are two main types of kidney failure: acute and chronic. Both have similar symptoms but each have their own distinct causes. When your dog’s kidneys stop working, the waste builds up in your dog’s body, causing the symptoms of increased thirst and urination.

Kidney failure and excess urea in the urine (kidney failure) is a common but serious disorder that causes your dog’s kidneys to stop working. Kidney failure can be acute or chronic and it can affect any breed of dog, no matter the age, sex, or health history. However, the acute form of kidney failure is most often caused by injury or toxic substance ingestion and the chronic form of kidney failure is more common in older dogs.

The symptoms of kidney failure depend on whether your dog has the acute or chronic form of the disease. Although some of the symptoms are similar, your dog’s medical history and age can help discern whether he is suffering from acute or chronic kidney failure. It is also important to know when the symptoms started and the how severe they are. In the acute form of kidney failure, the symptoms will come on suddenly, but chronic kidney failure comes on slowly and gradually, making it harder to discover. The symptoms of acute and chronic kidney failure are:

 Acute Kidney Failure

• Vomiting
• Diarrhea
• Appetite loss
• Extreme thirst
• Bad breath
• Fever
• Irregular heartbeat
• Sudden increased or decreased urination
• Excessive sleepiness

 Chronic Kidney Failure

• Extreme thirst
• Increased urination
• Drowsiness
• Lethargy
• Fever
• Bad breath
• Loss of appetite
• Weight loss
• Vomiting
• Runny/bloody stools
• Sores in the mouth
• Loss of energy

 Types

Acute Kidney Failure comes on suddenly and can happen in any breed, any age, no matter the sex, health, or medical history.

Chronic Kidney Failure comes on gradually and is usually seen in older dogs between 7 to 10 years of age. If a congenital disease causes the chronic kidney failure, the symptoms will start sooner, at approximately two years old.

The cause of excess urea in the urine is kidney failure, which causes kidney failure if not treated promptly. The problem is that by the time the symptoms and clinical signs, such as positive blood or urine tests, the kidney failure is usually too advanced to save your dog’s kidneys. Here are some causes of both acute and chronic kidney failure:

Acute Kidney Failure

• Injury
• Toxicity
• Poison
• Infection
• Kidney stones
• Ureteral stones
• Heat stroke

Chronic Kidney Failure

• Old age
• Infection
• Parasitic disease
• Cancer
• Amyloidosis
• Autoimmune disease
• Trauma
• Medication
• Poison
• Congenital defect or disease

To diagnose kidney failure from excess urea in the urine the veterinarian will first do a thorough physical examination. This exam will include blood pressure, body temperature, heart rate, eye and dental exam. It is important that you document and share all of the details of your dog’s symptoms, such as when they started, how they have progressed, and your dog’s medical history. The veterinarian will need to run some laboratory tests, such as:

• Blood chemistry panel (urea, nitrogen, creatinine, phosphorus)
• Packed cell volume (anemia)
• Urinalysis (specific gravity, protein, sediment)
• Complete Blood Count (CBC)

 It is also necessary to get other tests to help diagnosis, such as:

• Digital radiographs (shape and size of the kidneys)
• Intravenous pyelography (contrast dye x-ray)
• Ultrasound (density of the kidneys)
• Biopsy

Sometimes it may also be necessary to get a CT scan or MRI if the veterinarian suspects kidney stones or damage. Further tests may need to be done depending on the outcome of the laboratory test results and radiographs.

The treatment for acute and kidney failure depend on what is causing the failure. Unfortunately, it is common that by the time the symptoms of kidney failure are noticed the kidneys are too damaged to save. There are no treatments to repair a damaged kidney, but there are some treatments that can be done to prevent any further damage; and if treated early enough, your dog can live for a few more years.

Some of these treatments are:

Acute Kidney Failure

• Toxicity and poisoning must be treated with a gastric lavage and fluid therapy immediately. This includes a hospital stay for at least 24 hours to restore the balance of electrolytes and chemicals in your dog’s circulatory system.
• Infection has to be treated with an aggressive round of IV antibiotics and fluid therapy in the hospital. Diuretic therapy is also needed to flush any toxins out of your dog’s body that the kidneys have not been able to get rid of. Once your dog’s body is flushed and hydrated, he may be able to go home with strict instructions to monitor his fluid intake and urine output.
• Kidney transplant is also a choice for those dogs who are still relatively healthy and young, but the success rate is low since this is a new procedure and it is very expensive.

Chronic Kidney Failure

• Hospitalization and IV fluid therapy with dialysis to flush the kidneys and get them started working again. Depending on the cause of the kidney failure, the treatment may only be needed once and your dog may be fine for years.
• Medications, such as calcitriol, or potassium therapy are an option in some cases. Nausea medication, blood pressure regulators, and anemia medicine can also be helpful in certain situations.
• Kidney transplant is usually not a choice in chronic kidney failure because it is not usually successful.

The recovery or your dog depends on the type and cause of the kidney failure, as well as how far the disease has progressed. If your dog has acute kidney failure that can be treated and his kidneys are still able to function normally, the prognosis is great. Your dog should live a long and healthy life with no lasting effects.

 If the vet diagnoses your dog with chronic kidney disease, he will continue to get worse until his kidneys are unable to function at all. It could be weeks or years, depending on the cause and the stage of the disease. No matter whether it is acute or chronic kidney disease, you should continue with any treatment your veterinarian prescribes as well as providing a healthy diet and regular check-ups.