Kidney Disease in Dogs

Overview:

Kidney disease is a common disorder in dogs which can be congenital or acquired. When kidneys malfunction, wastes build up in the blood.

Each kidney has tiny filtering units called nephrons. Blood passes through the kidney & is filtered by the nephrons. They reabsorb what is needed & the waste is excreted in the urine. When nephrons die the remaining ones have to work harder to maintain function. Kidney disease becomes apparent when 70% of the kidney function has been lost.

As dogs age, their chances of developing chronic kidney disease increase.

What do kidneys do?

• Kidneys help control blood pressure by releasing an enzyme called renin. When blood pressure drops and kidneys don’t receive enough blood, renin is released; causing blood vessels to contract (tighten). When blood vessels contract, blood pressure goes up.

• Kidneys filter waste products & excess water from the blood. The cleaned blood stays in the body & the waste products leave the body in urine.

• Stimulation of red blood cell production.

• They help maintain the proper balance of acid and minerals, including sodium, calcium, potassium and magnesium, in the blood.

What causes kidney disease in dogs?

There are many causes of kidney disease in dogs. Because the kidneys filter the blood, other diseases & infections can damage the kidneys. You will notice that some causes are seen in both acute & chronic kidney failure.

Acute Kidney Failure (Acute Renal Failure or ARF):

Acute kidney failure is brought about by a sudden decline in kidney function.

• Poisoning (ingestion of a toxic substance such as anti-freeze or poisonous plants)

• Heatstroke

• Blockage

• Infection

• Some medications

• Dehydration

• Cancer

Chronic Renal Failure:

Slow & progressive.

• Diabetes

• Infection

• Hypertension

• Dental disease

• Polycystic kidney disease

• Infections

• Congenital defects

• Cancer of the kidneys

What are the symptoms of kidney disease in dogs?

• Weight loss

• Depression

• Vomiting

• Polyuria (excessive urination)

• Polydipsia (excessive thirst)

• Lethargy

• Enlarged kidneys

• Bad breath

• Weakness

• Loss of coordination

How is kidney disease in dogs diagnosed?

Your veterinarian will perform a thorough physical examination & take a medical history of your dog. Some tests he/she may run include; 

• Complete blood count

• Blood samples will be taken for testing. Elevated blood urea nitrogen (BUN) and creatinine are both indicative of renal failure.

• Urinalysis will be able to provide additional information on the extent of kidney damage, urine-concentrating ability & if an infection is present in the urinary tract.

• Urine specific gravity: This test is to check to see how concentrated the urine is.

• Kidney ultrasound or X-ray

• Kidney biopsy

How is kidney disease in dogs treated?

• Administration of fluids subcutaneously to treat dehydration.

• Prescription diet: Such a prescription diet contains a lower percentage of protein & less phosphorus than normal dog food. Dogs need protein every day for growth, building muscles & repairing tissue. After the body uses the protein in the foods, a waste product called urea is made. Dogs with kidney failure are not able to get rid of this urea normally. Damaged kidneys may not be able to remove phosphorus from the blood. This causes the level of phosphorus in the blood to become too high. A high blood phosphorus level may cause the dog to lose calcium from their bones.

• Phosphorus binders may be given. These come in tablet or capsule form.

• High blood pressure (hypertension): Medication may be prescribed if your dog's blood pressure is too high.

• Antacids & anti-nausea medication.

• Erythropoietin: The kidneys produce a hormone, erythropoietin, which instructs the bone marrow to produce red blood cells. Dogs with kidney failure often have a low red blood cell count. Only the human form is available & some dogs may eventually recognise this substance as foreign & antibodies will be created against it.

Please note:

The medical articles on this site have not been written by a veterinarian & should not be considered a replacement for a veterinarian visit. The articles are provided for informative purposes only.

Always seek immediate veterinary advice for any problems (health or behavioral) in your pets. 

While great care has been made in the creation of these articles, we cannot guarantee the accuracy or omissions on these pages. If in any doubt whatsoever, seek professional medical advice.