Kidney Disease in Dogs and Cats > Testing for Kidney Failure
Canine and feline kidney failure can be a devastating disease for dog and cat owners and for their pets. There are many different tests that are used to diagnose and monitor the progress of kidney failure.
Changes in Blood Values in Canine and Feline Kidney Failure
A routine blood screen typically includes a complete blood count and a blood chemistry profile. The complete blood count examines red blood cell and white blood values, looking for evidence of anemia, infection and other abnormalities. The blood chemistry profile allows examination of tests that help determine whether internal organs, such as the kidneys and liver, are functioning normally.
The blood chemistry profile measures, among other values, the blood urea nitrogen (BUN) and creatinine. Blood urea nitrogen (BUN) and blood creatinine levels are used to measure the body waste products that are present in your pet's blood stream. The higher these levels are, the more waste products are present. Abnormally high BUN and creatinine values indicate kidney disease. They are two of the most useful values for diagnosing kidney failure in dogs and cats.
Blood urea nitrogen and creatinine can also be used to monitor the progress the disease. Decreasing values may indicate an improvement in the progress of kidney disease. Conversely, increasing values may mean that that your dog or cat's kidney failure is progressing and getting worse.
Despite the importance of BUN and creatinine in diagnosing and monitoring kidney failure , there are also several other tests that are used to properly diagnose and monitor kidney failure in dogs and cats.
Blood electrolytes such as calcium, phosphorus and potassium need to be monitored in addition to the BUN and creatinine. The blood levels of calcium, phosphorus and potassium may affect the treatment of dogs and cats with kidney failure. These values are easily measured as part of the blood chemistry profile, along with the blood urea nitrogen and creatinine.
Red blood cell values should be examined for signs of anemia. Red blood cell values are measured as part of the complete blood count. Anemia is evidenced by lower than normal hematocrit, red blood cell and hemoglobin values. Anemia is a common occurrence in kidney failure and may require treatment, especially in cases of chronic kidney failure.
Urine Testing in the Diagnosis of Canine and Feline Kidney Disease
Urine testing, often called urinalysis, is also an important part of both diagnosing kidney failure and monitoring its progress.
- Urine specific gravity monitors the ability of the kidneys to concentrate urine. As kidney failure becomes more advanced, the kidneys lose their ability to concentrate urine. Low urine specific gravity values, when persistent, are consistent with kidney failure.
- The amount of urine that your pet produces should be monitored as well. Increased urine output indicates ongoing fluid loss and may mean that fluid therapy is required to combat dehydration. Fluid therapy is almost always mandatory in acute kidney failure and may be necessary periodically in chronic kidney failure.
- Urine protein levels need to be measured to assess the degree of protein loss through the kidneys. When the kidneys fail, they lose the ability to filter properly. Protein is often lost in the urine as a result of kidney failure.
Your veterinarian may also recommend doing a urine culture to determine if there is infection present.
Measuring Blood Pressure in Dogs and Cats with Kidney Failure
Blood pressure should be monitored in all dogs and cats suffering from kidney failure. Hypertension (high blood pressure) is common in kidney failure and may need to be treated if the blood pressure is severely elevated. If left untreated, hypertension can contribute to the damage done by kidney failure.
More: Kidney Disease in Dogs and Cats - Signs, Treatment, Diagnosis