Understanding Dog Kidney Failure: Stages Chart & Resources
What is Dog Kidney Failure?
Dog kidney failure, also known as canine renal failure, refers to the inability of the kidneys to adequately perform their vital functions. It is a serious and potentially life-threatening condition that can be either acute or chronic.
Acute Kidney Failure
Acute kidney failure occurs suddenly and often results from a specific event or condition, such as ingestion of toxins, severe dehydration, urinary blockage, or a sudden decrease in blood flow to the kidneys.
However, it can be reversible if promptly diagnosed and treated.
Chronic Kidney Failure
Chronic kidney failure, on the other hand, develops gradually over time, usually due to progressive and irreversible damage to the kidneys.
It is more common in older dogs, and is also is often attributed to underlying conditions like:
- kidney disease
- congenital abnormalities
- immune-mediated diseases
- long-term exposure to certain medications or toxins.
In this article, we will be discussing the different stages of chronic kidney disease.
Veterinary Testing for Dog Kidney Disease
Veterinarians use several tests to diagnose kidney disease in dogs. The tests help your veterinarian evaluate the overall kidney function and also determine the underlying cause of the disease.
Common Diagnostic Tests
Some common diagnostic tests include:
- Blood tests: Blood tests provide valuable information about kidney function and also help identify markers of kidney disease.
- Blood urea nitrogen (BUN): Elevated BUN levels indicate impaired kidney function.
- Serum creatinine: Increased creatinine levels suggest reduced kidney function.
- Symmetric dimethylarginine (SDMA): SDMA is a more sensitive and specific marker for kidney disease compared to traditional markers like BUN and creatinine. SDMA is a waste product that is produced during the breakdown of proteins in the body. Normally, the kidneys filter out SDMA, and it is excreted in the urine. When the kidneys are not functioning properly, SDMA levels in the blood increase, indicating reduced kidney function. The SDMA test can detect kidney disease earlier than other traditional markers because it can detect subtle changes in kidney function. It helps identify kidney disease in its early stages, even before other markers like BUN and creatinine become elevated.
- Urinalysis: Urinalysis involves analyzing a urine sample to check for abnormalities. It helps evaluate the concentration of urine, presence of protein, blood, and other substances. Abnormal findings can indicate kidney damage.
- Urine protein-to-creatinine ratio (UPC): This test measures the ratio of protein to creatinine in the urine. Elevated UPC values suggest protein loss through the kidneys, therefore indicating kidney damage or disease.
- Imaging tests: Imaging tests, such as ultrasounds or radiographs (X-rays), can provide detailed images of the kidneys. They help identify structural abnormalities, kidney stones, or other conditions that may be causing kidney disease.
- Blood pressure measurement: High blood pressure can be a sign of underlying kidney disease. Measuring blood pressure can also help diagnose and monitor kidney disease.
- Additional blood tests: Depending on the suspected cause or type of kidney disease, your vet may also recommend additional blood tests. Your veterinarian might also include tests for infectious diseases, immune-mediated disorders, or specific biomarkers related to certain kidney diseases.
- Kidney biopsy: In some cases, a kidney biopsy may also be necessary to determine the exact cause and severity of kidney disease. A biopsy involves obtaining a small sample of kidney tissue for microscopic examination.
The specific tests your vet chooses may vary depending on your dog's individual case and health assessment.
If you suspect your dog has kidney disease, it's best to consult your veterinarian for a proper diagnosis and appropriate treatment.
Dog Kidney Failure Stages Chart
Stage I (Early Stage)
Stage I kidney disease is the same as early stage kidney disease. Many dogs don't display any symptoms at all during the early stages of kidney failure.
You may or may not notice a mild increase in water consumption (polydipsia) and urination (polyuria), but no change in appetite or behavior.
Kidney damage may be present, but your dog compensates well and lab results may still be in the "normal" range.
Stage II (Mild)
Stage II Kidney Disease is mild kidney disease. You dog may or may not show signs and symptoms.
However, the signs and symptoms of Stage II Kidney Disease are often the same signs displayed as a dog ages.
Common signs include:
- Increased drinking and urinating
- Slight decrease in appetite
- Mild weight loss
- Occasional vomiting or diarrhea
- Slight decrease in energy levels
- Blood tests may show mild elevations in blood urea nitrogen (BUN) and serum creatinine levels
Stage III (Moderate)
Stage III Kidney Disease is moderate kidney disease.
Now, all signs, symptoms and lab results all indicate kidney disease.
Common signs include:
- Further increase in drinking and urinating
- Decreased appetite
- Weight loss becomes more pronounced
- Lethargy and weakness
- More frequent vomiting and diarrhea
- Bad breath and oral ulcers may develop
- Blood tests show elevated BUN and serum creatinine levels
Stage IV (Severe)
Stage IV Kidney Disease is severe kidney disease. At this point, the disease has taken a noticeable toll on your dog's health.
Common signs include:
- Excessive drinking and urinating
- Significant decrease in appetite, possibly anorexia
- Pronounced weight loss and muscle wasting
- Severe lethargy and weakness
- Frequent vomiting and diarrhea
- Signs of dehydration (sunken eyes, dry gums, loose skin)
- Pale mucous membranes from anemia
- Oral ulcers and bad breath
- High blood pressure (hypertension) may occur
- Blood tests show markedly elevated BUN and serum creatinine levels
In advanced stages, your dog may also experience complications such as electrolyte imbalances, high blood pressure, anemia, and secondary infections.
Please remember, the above symptoms are merely general guidelines. Also, the presence and severity of symptoms can vary from dog to dog.
If you suspect your dog has kidney disease or notice any changes in their behavior or health, it's crucial to consult a veterinarian for a thorough examination, proper diagnosis, and appropriate treatment.
Early detection and intervention will help manage kidney disease more effectively and also help improve your dog's quality of life.
What You Can Do to Help
If your dog has kidney disease, it's crucial to work closely with your veterinarian.
Your vet will help you monitor the status of your dog's kidney health using bloodwork and other testing.
In addition, there are many things you can do at home to help keep your dog's kidneys healthy.
The most important step during all stages of kidney failure is keeping your dog hydrated.
You can also help with food changes, lifestyle changes, and special supplements and herbs.
If you want to be proactive in your dog's health care, then read Here's What to Feed a Dog with Kidney Disease. If offers information on different things you can do to help your dog feel better and have an overall better quality of life.
- Buzby, J. (2022). Kidney Disease in Dogs: Stages and What They Mean For Your Dog. Dr. Buzby’s ToeGrips for Dogs. https://toegrips.com/kidney-disease-in-dogs-stages/
- IRIS Kidney - Guidelines - IRIS Treatment Recommendations. (n.d.). http://www.iris-kidney.com/guidelines/recommendations.html
- Woodnutt, J., & Woodnutt, J. (2022). Kidney Failure in Dogs: Signs, Causes, and Treatment. The Vets. https://thevets.com/blog/kidney-failure-in-dogs/