Inherited defects only affect the very young, so I'll leave them out of the current discussion. Signs and recognition of decreased kidney function are not evident until at least two-thirds of the total kidney function has been lost. Once kidney damage occurs, the kidney tissue does not regenerate. Unfortunately, most kidney disease tends to be progressive. Therefore, any measure that your pet's doctor takes to prevent the disease, delay the onset of kidney problems or to slow progression of the disease will help a pet live longer.
Veterinarians first see signs of loss of appetite, yet remaining thirst in the affected pets.
Depression, dull hair coat and possibly vomiting may be seen in these pets too. Contrary to conventional wisdom, these pets may still urinate, sometimes even frequently according to the stage of disease they are in. Therefore, the urine ultimately becomes clear and watery when it is produced. As you would guess, urine testing is one way to analyze kidney disease in your pet. Blood analysis of key tests such as the BUN, Creatinine, Total Protein and Phosphorous all help in confirming the diagnosis and degree of kidney damage.