Your cat's kidneys perform many important functions. They filter out toxins and waste products in the blood, regulate sodium levels in the bloodstream, regulate calcium and vitamin D levels, and trigger new red blood cell production. Unfortunately, kidney disease is the primary disease observed in older cats. A progressive disease measured in severity from Stage I to Stage IV, kidney failure is tracked via regular monitoring of creatinine and protein levels in the urine. Clinical signs such as increased thirst and urination, nausea and vomiting normally become apparent in Stage III and grow acute during Stage IV.
Stage III Kidney Disease
In order to maintain health, cats require only 25 percent of total kidney function. Once a cat has entered Stage III, also called early kidney failure, his kidneys are functioning only between 15 and 25 percent. At this stage, laboratory testing reveals levels of the waste product creatinine between 3.0 and 6.0 accompanied by abnormal electrolyte levels. Visible clinical signs of Stage III feline kidney disease include increased thirst and urine production, and gastrointestinal issues. Increased nausea and vomiting normally create a loss of appetite. The cat may develop high blood pressure or experience bladder infections.
Treating Stage III Cats
Administration of subcutaneous fluids, the primary treatment for cats experiencing early kidney failure, can be performed at home. Your veterinarian will teach you how and when to administer these fluids. Injected beneath the skin, usually at the back of the neck, these fluids help keep your cat hydrated as his urine production increases and eases the strain on the kidneys by diluting the blood. Depending upon your cat's individual needs, your veterinarian may recommend electrolyte supplements, a low-protein kidney diet, anti-nausea medications, steroid treatments or appetite stimulants. The goal of treatment for cats in Stage III kidney disease is to prolong life while maintaining quality of life.
Stage IV Kidney Disease
A cat enters Stage IV kidney failure, also called end-stage kidney failure, when his kidneys begin functioning below 15 percent. Laboratory testing reveals creatinine levels above 6.0, usually accompanied by elevated phosphorous levels. Cats in end-stage kidney failure experience extreme nausea and lethargy, sometimes accompanied by a refusal to eat.
Choosing a Stage IV Treatment
Cats in Stage IV kidney disease normally live only a few months at most. At this point, you must consult your veterinarian to determine the best course of action. Since kidney damage can't be reversed, the focus of care revolves entirely around quality of life. Administration of intravenous fluids, designed to decrease creatinine levels and reduce nausea, may provide some relief from symptoms and make your cat more comfortable. Your veterinarian may recommend continuation of medications, depending upon your cat's response to those treatments. Your veterinarian may recommend euthanasia as a humane choice for your cat if palliative care can't sufficiently alleviate his symptoms.