Acute Renal (Kidney) Failure in Cats

Acute kidney failure (acute renal failure or ARF) is characterized by an abrupt decline in kidney function that leads to changes in the chemistry of the body including alterations in fluid and mineral balance. The changes that arise as a result of ARF affect almost every body system.

The kidneys filter blood, remove the waste products of metabolism, and eliminate them in the urine. The kidneys also regulate the volume and composition of body fluids (including mineral concentrations and acid base balance), and produce hormones that stimulate the production of red blood cells (erythropoietin) and regulate calcium balance (calcitriol).

Acute kidney failure can be caused by toxic injury to the kidneys, decreased blood flow and oxygen delivery to the kidneys, infections, obstruction of the kidneys and prevention of urine elimination caused by a ruptured bladder.

The recent recognition of kidney failure is not necessarily the same as acute renal failure, since some animals with chronic kidney failure tolerate it for some time before symptoms are apparent.

There is no specific breed predilection but older animals are thought to be at greater risk for acute kidney failure. Acute kidney failure is more common in the fall and winter due to pet exposure to anti-freeze which contains ethylene glycol. Cats that are allowed to roam outside without supervision potentially have increased exposure to ethylene glycol.

The symptoms of ARF, although often severe, are not specific. Even with intensive management, ARF is a very serious disorder and often is fatal.

What to Watch For

Disorientation

Incoordination

Decreased urine production

Straining to urinate

Loss of appetite

Lethargy

Vomiting

Weakness

Changes in water consumption and urination

Diagnosis

Your veterinarian will take a complete medical history specifically questioning exposure to ethylene glycol (anti-freeze), recent surgery or anesthesia (possibly causing decreased blood flow to the kidneys), exposure to drugs toxic to the kidneys (aminoglycoside group of antibiotics and non-steroidal anti-inflammatory drugs) and previous illnesses. The following diagnostic tests may also be necessary to recognize acute kidney failure and exclude other diseases. Tests may include:

Complete physical examination

Serum biochemistry tests

Urinalysis

Complete blood count

X-rays of the abdomen

Culture of the urine

Ultrasound examination

Kidney biopsy

Ethylene glycol test

Blood tests for certain infections

Treatment

ARF is a life-threatening serious condition that requires hospitalization and intensive treatment. Treatment consists of identification and correction of life-threatening problems while searching for the underlying cause of ARF. Treatment for ARF may include one or more of the following:

Induce vomiting

Intravenous fluids

Drugs that encourage urine production

Management of blood electrolyte abnormalities

Monitor urinary output

Control of vomiting

Management of anemia

Peritoneal dialysis or hemodialysis

Treatment with 4-methylpyrazole (Antizol®) or ethanol

Home Care

Acute renal failure is a life-threatening condition and there is no effective home treatment. If you suspect your pet has this condition, or if you even suspect your pet may have consumed even a small amount of anti-freeze, you should call your veterinarian immediately. Your veterinarian may instruct you to induce vomiting before bringing your pet to the hospital.

Administer any medications prescribed by your veterinarian. Follow-up examinations and laboratory tests are important to assess your pet's response to treatment. Allow free access to fresh clean water.

Preventative Care

Avoid exposure to ethylene glycol (anti-freeze), and avoid exposure to drugs known to be toxic to the kidney (e.g. aminoglycoside antibiotics and non-steroidal anti-inflammatory drugs). Don't allow cats to roam outside unattended.