Acute kidney failure is a sudden loss of function that is sometimes but not always reversible. Chronic kidney failure is an irreversible loss of function that occurs gradually over months or years. Failing kidneys can't adequately clear the blood of certain toxins. As a result, when the kidneys fail, there is an abnormally high levels of these wastes products. Failing kidneys may also produce extremely dilute urine or urine that contains too much protein.
Healthy kidneys produce concentrated urine that is relatively protein-free.
To determine the prognosis of kidney disease, blood and urine tests are performed frequently during treatment to evaluate how well the kidneys are responding. It's a good sign if test results swing back toward normal within the first 48 to 72 hours of therapy. Initial test results can be remarkably similar for both forms of kidney failure. The diagnostic challenge is to determine whether the dog has acute or chronic kidney failure. At our practices, we recommend yearly base line lab testing starting at age 3.