Early Signs of Kidney Disease
Race Foster, DVM
Drs. Foster & Smith, Inc.
The kidneys are essentially the filters of the body system and renal failure, if not diagnosed quickly and treated aggressively, can lead to a total breakdown of the body, and eventually, death.
Functions of the urinary system
The kidneys are a major part of the urinary system. The urinary system includes the kidneys, the ureters (the tubes from the kidneys to the urinary bladder), the urinary bladder, and the urethra (the tube from the urinary bladder to the outside). Functions of the urinary system include:
- Removal of waste products from the blood and then from the body
- Regulation of the volume of body fluid
- Maintenance of pH balance, sodium and potassium levels in the body
- How renal disease affects pets
Renal disease or failure can have an acute (sudden onset) form, which is sometimes reversible, or a chronic (slow and usually progressive) form which is irreversible but can often be managed successfully. Although all breeds and ages can suffer the effects of both types, older pets are at higher risk of the chronic form.
Acute renal failure (ARF)
ARF is less common than chronic renal failure and usually has precipitating factors such as ingestion of a toxin. There are many precursors of ARF, including heatstroke, reaction to other body system failures, certain medications, and diseases such as feline infectious peritonitis (FIP). The incidence of ARF is much more common in fall and winter months when animals are exposed to and ingest antifreeze containing ethylene glycol, a major cause of ARF.
Chronic renal failure (CRF)
CRF results from kidney disease that has been persisting for months or years. It is irreversible and renal function deteriorates progressively over the course of the disease. Cats with mild CRF may not exhibit symptoms. Almost twice as many cats as dogs are diagnosed with CRF.
Warning signs of ARF and CRF
Since our cats cannot tell us when they hurt, we must rely on our observations to let us know when something is wrong with the kidneys. Cats may have:
- Changes in urinary habits such as urinating a lot (polyuria) or not at all (anuria)
- Increased water consumption (polydipsia)
- Anorexia (not wanting to eat)
- Listlessness
- Vomiting or diarrhea, which may or may not be bloody
- Ataxia (stumbling as the result of loss of voluntary movement)
- Seizures or blindness
- Anemia and resulting weakness
- Known or suspected toxin exposure
In addition, cats with CRF may experience weight loss, poor hair coats, and often develop high blood pressure.
With either form, symptoms get worse as the disease progresses. If you notice any of the above signs, schedule a visit with your veterinarian as soon as possible. Early diagnosis of acute renal failure will greatly influence the success of the treatment. Cats with chronic renal failure, if managed successfully through diet, hydration therapy, and medications, can often live for years with the disease.
