Kidney Disease in Dogs

Kidneys are small yet mighty organs that work hard to keep a dog healthy. For example, kidneys regulate blood pressure and electrolyte levels, filter waste from the blood, and produce urine.

Anything that affects the kidneys could spell bad news for a dog’s health and quality of life.

Kidney disease can make dogs feel lousy and, if acute, be life-threatening if not treated quickly and aggressively.

Though kidney disease affects only about 1 percent of dogs¹, knowing about it can help you get your dog the treatment they need if their kidneys aren’t working well.

What is Kidney Disease in Dogs?

Kidney disease is a broad term describing any dysfunction of the kidneys. It is classified as acute or chronic. Acute kidney disease develops rapidly, while chronic kidney disease (CKD) develops slowly over a few weeks to a few years. Interestingly, acute kidney disease can progress to CKD.

Any age of dog can develop kidney disease. However, CKD is more common in older dogs.

When the kidneys stop working well, waste products normally removed by the kidneys accumulate in the blood. In addition, electrolyte levels become imbalanced, blood pressure increases, and red blood cell production decreases.

What Are the Causes of Kidney Disease in Dogs?

Causes of kidney disease are generally categorized according to whether the kidney disease is acute or chronic.

Acute kidney disease in dogs is commonly caused by ingesting something toxic to the kidneys, such as antifreeze, raisins, grapes, or aspirin. Other causes of acute kidney disease include bacterial infections, severe dehydration, heat stroke, and urinary tract blockage.

CKD in dogs is an old-age change. Kidney cells can wear out as dogs age, leading to decreased kidney function.

Kidney disease can also be an inherited condition. For example, a genetic disorder may cause a dog to be born without one or both kidneys. 

What Are the Symptoms of Kidney Disease in Dogs?

Symptoms of kidney disease in dogs develop rapidly with acute kidney disease and gradually with CKD. 

However, these symptoms aren’t immediately apparent because the kidneys can continue functioning quite well even with significant damage. Symptoms don’t become noticeable until nearly 75 percent of kidney function is compromised.²

Here are the early signs of kidney disease:

• Lethargy
• Depressed mood
• Increased urination
• Increased water consumption

As kidney disease progresses, dogs get sicker and show other symptoms, such as:

• Nausea
• Vomiting
• Seizures
• Pale gums
• Bad breath
• Weight loss
• Mouth ulcers
• Incoordination
• Reduced appetite
• Blood in the urine
• Reduced amount of urine or no urine

Diagnosing Kidney Disease in Dogs

Diagnosing kidney disease in dogs is a process. First, your veterinarian will take a detailed history from you and perform a complete physical exam. Provide as much information as possible, including your dog’s symptoms and if your dog ate anything toxic.

Next, your veterinarian will perform blood work and a urinalysis, both of which can provide important clues indicating kidney disease. Blood work findings suggesting kidney disease include increased blood urea nitrogen, creatinine, and electrolytes like potassium and sodium. Red and white blood cell levels may also be abnormal with kidney disease.

A urinalysis involves several tests to diagnose kidney disease:

• Urine culture to look for bacteria
• Identification of blood, protein, or both in the urine
• Urine specific gravity to measure urine concentration

Abdominal X-rays and an abdominal ultrasound may also be performed to evaluate the appearance of your dog’s kidneys. 

Because kidney disease affects blood pressure, your veterinarian may also take your dog’s blood pressure.

Your veterinarian will analyze all test results to diagnose and stage your dog’s kidney disease (if your dog has CKD), then develop a personalized treatment plan.

What Are the Stages of Kidney Disease in Dogs?

Kidney disease in dogs, specifically CKD, is classified according to a staging system developed by the International Renal Interest Society (IRIS). IRIS staging, performed after kidney disease is diagnosed, allows veterinarians to determine a specific treatment and monitoring plan according to disease severity.

Blood creatinine and SDMA, defined below, are measured to determine the stage of CKD. The staging system ranges from 1 (least severe) to 4 (most severe). 

• Blood creatinine: Creatinine is a waste product from the muscles. Levels are increased with CKD.
• Blood SDMA: SDMA is an amino acid removed by the kidneys as a waste product. Levels are increased with CKD.

The IRIS staging system also includes substages, which consider blood pressure and the ratio of protein to creatinine in the urine.

Treating and Managing Kidney Disease in Dogs

Treating kidney disease depends on several factors: overall health, type and severity of kidney disease, and underlying cause if present. Early treatment gives dogs with kidney disease the best chance to recover and enjoy a good quality of life. However, treatment will be ineffective if the kidneys are irreparably damaged. 

Let’s go through treatment for acute kidney disease and CKD.

Acute kidney disease treatment

Acute kidney disease can quickly turn into an emergency. It is reversible, but treatment must be early and aggressive to reverse kidney damage.

Intensive care may be needed, which includes intravenous fluid therapy, antibiotic therapy if a bacterial infection is present, and a feeding tube if a dog refuses to eat. Dialysis may also be needed to filter waste from the blood. 

Dogs with acute kidney failure are continuously monitored to ensure they recover and respond well to treatment.

CKD treatment

CKD is not curable, but it is manageable. Treatment for CKD aims to reduce the kidneys’ workload, filter waste from the blood, and return electrolyte levels to normal. Treatment options include specialized diets, dialysis, nutritional supplements, and medications.

There are many medications that a dog with CKD may need. Examples include:

• Erythropoietin to promote red blood cell production
• Blood pressure medicine to reduce blood pressure
• Phosphate binders to remove phosphorus from the blood

At-home fluid therapy, administered subcutaneously (under the skin), may also be needed to ensure your dog stays adequately hydrated. Your veterinarian will let you know how much fluid your dog needs and how often to administer it.

Treatment for CKD is long-term and must be consistent to effectively manage the disease and keep your dog feeling as well as possible.

Whether the kidney disease is acute or chronic, dogs with kidneys that are no longer functioning need a kidney transplant. 

Throughout treatment, follow-up appointments are needed to monitor your dog’s blood work and urine. Your veterinarian will adjust the treatment plan according to your dog’s response to treatment and disease progression.

Cost to Treat Kidney Disease

Costs for kidney disease treatment can quickly add up, especially if your dog needs hospitalization and intensive care. Examples of treatment expenses are listed below:

• Medication
• Fluid therapy 
• Specialized diet
• Kidney transplant
• Nutritional supplements
• Follow-up appointments
• In-hospital monitoring and testing

How to Prevent Kidney Disease in Dogs

Blocking access to kidney-toxic substances is key to preventing acute kidney disease. Be aware that 100 percent prevention of acute kidney disease is not practical.

CKD is not preventable because it is an old-age change. Feeding your dog a healthy diet, staying up-to-date on your dog’s vaccinations, and taking your dog for annual wellness visits will help keep your dog (and your dog’s kidneys) healthy for as long as possible.

Kidney Disease in Dogs Infographic

REFERENCES

1. Foley P; DACVIM (Small Animal Internal Medicine). BSAVA Manual of Canine and Feline Nephrology and Urology, 2nd ed. Can Vet J. 2008;49(3):291.
2.  Polzin DJ, Ettinger SJ: Chronic Kidney Disease. Textbook of Veterinary Internal Medicine, 7th ed. St. Louis, Saunders Elsevier 2010 pp. 1990-2021.