Acute Renal Failure in Ferrets

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 and produce hormones that stimulate the production of red blood cells and regulate calcium balance.

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.

Acute kidney failure can be caused by toxins, decreased blood flow to the kidneys, obstruction of the urethra or bladder rupture.

There is no specific predilection but older ferrets are thought to be at greater risk for acute kidney failure.
What to Watch For

• Loss of appetite
• Lethargy
• Vomiting
• Weakness
• Changes in water consumption and urination

Within several hours of ingesting a kidney toxic substance, disorientation and incoordination may be observed. Severe cases of ARF are associated with severely decreased urine production (called oliguria) or cessation of urine production (called anuria).

Ferrets with ARF caused by obstruction of the urethra typically strain as they attempt to urinate and seem very painful. Pets with ARF due to rupture of the bladder may not show signs of straining to urinate. ARF often is fatal unless managed quickly. Even with intensive management, ARF is a very serious disorder and often is fatal.

Diagnosis

Diagnostic tests are needed to recognize acute kidney failure and exclude other diseases. Tests may include:

• Complete medical history specifically questioning recent surgery or anesthesia, exposure to drugs toxic to the kidneys and previous illnesses
• Complete physical examination including palpation of the abdomen to evaluate the kidneys and bladder
• Serum biochemistry tests to evaluate kidney function (such as blood urea nitrogen or BUN, serum creatinine, and serum phosphorus)
• Urinalysis to evaluate urine concentration and the presence of crystals
• Complete blood count to evaluate for infection, inflammation or anemia
• X-rays of the abdomen to evaluate kidney size

In a few cases, additional tests may be recommended:

• Culture of the urine to identify bacterial infection
• Ultrasound examination to evaluate the kidneys and bladder
• Kidney biopsy to differentiate acute from chronic kidney failure
• Blood tests for certain infections

Treatment

Treatment for ARF may include one or more of the following:

• 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. The prognosis for recovery of kidney function in ARF depends on the severity of the kidney damage, the underlying cause of ARF and supportive treatment.
• Intravenous fluids must be administered cautiously to prevent excessive fluid retention (called overhydration).
• Drugs that encourage urine production (e.g. furosemide, dopamine) may be given.
• Management of blood electrolyte abnormalities such as high blood potassium concentration (i.e. hyperkalemia) and metabolic acidosis may be necessary.
• Urine output must be carefully monitored to assess the pet’s response to treatment and to prevent overhydration during intravenous administration of fluids.
• Control of vomiting may be necessary.

Home Care and Prevention

Acute renal failure is a life-threatening condition. If you suspect your pet has this condition, you should see your veterinarian immediately. There is no effective home treatment for this condition.

Always provide plenty of fresh clean water and avoid exposure to drugs known to be toxic to the kidney such as ibuprofen.