Kidney disease, which is potentially life-threatening, can occur in cats for many reasons and tends to develop as cats advance in age. However, regardless of the cause, the symptoms of kidney disease are the same, and they usually are nonspecific. In most cases, kidney disease cannot be cured but often can be managed with early diagnosis and prompt, lifelong medical treatment. Early diagnosis and intervention may help curb further damage to the organs in acute cases. However, particularly in chronic cases, the kidneys typically are severely and irreversibly damaged by the time clinical signs appear.
Symptoms of Kidney Disease
The kidneys are responsible for filtering nitrogenous waste products from circulation and excreting them in urine, regulating the concentrations of hydrogen, sodium, potassium, phosphate and other components of bodily fluids and producing essential hormones. Once a significant portion of functional kidney tissue has been damaged, the cat becomes increasingly unable to filter and excrete waste products in its urine, and toxic levels build up in the blood, causing signs of disease.
The most consistent and common clinical signs of kidney disease are polyuria (markedly increased urination) and polydipsia (markedly increased water consumption). These signs are a result of the body’s attempt to flush toxic wastes out of circulation. Owners will report unusually frequent visits by their cat to the litter box. As the kidneys progressively deteriorate, the urine becomes less concentrated and lighter in color. Other common signs of renal disease include depression, appetite loss, weight loss, lethargy, weakness, possible tooth discoloration, vomiting, diarrhea, dehydration, oral ulcers, bad breath (halitosis), reluctance to exercise, pale gums, shivering, seizures, muscle wasting and abdominal discomfort. Kidney disease can also cause high blood pressure, which can result in blindness. Owners may notice a drastic change to the appearance of their cat’s eyes, such as enlarged pupils and an overall cloudy appearance.
Chronic kidney disease cannot be cured. However, in many cases it can be controlled with medication, diet and other supportive therapies that will help clear the body of waste build-up.