Nephrotic Syndrome in Dogs

Symptoms of nephrotic syndrome include:

• Uncomfortable breathing
• Swelling in limbs
• Swelling in the skin in neck, thorax, and abdomen
• Abdominal distention due to fluid accumulation
• Paralysis of the hind legs
• Excess of fats in blood
• High blood pressure
• Abnormal blood clots

Additional symptoms related to the conditions that cause nephrotic syndrome, namely glomerulonephritis, proteinuria, hypoalbuminemia, and hyperlipidemia, can include:

• Blood in the urine
• Lethargy
• Anorexia
• Decreased appetite
• Increased thirst
• Increased urination
• Discolored urine, usually pink or red
• Strained urination
• Weight loss
• Vomiting
• Chronic kidney failure
• Diarrhea
• Abdominal pain
• Creamy colored blood vessels in the eyes
• Hypotension
• Decreased cardiac output
• Seizures

Nephrotic syndrome is a rare complication that can develop from the kidney diseases:

• Glomerulonephritis
• Amyloidosis

These conditions need to be present for nephrotic syndrome to occur:

• Proteinuria 
• Hypoalbuminemia
• Hyperlipidemia
• Accumulation of fluid in interstitial spaces, such as the abdomen

Treatment of nephrotic syndrome will attempt to resolve symptoms and treat any underlying cause of the condition.

The abnormal swelling is treated through fluid removal only when the dog is in discomfort or in a life-threatening condition. Care is taken, as repeated fluid removals can result in other conditions, such as hyponatremia and hyperkalemia. Diuretic therapy can be initiated, adjusting the dose to minimize further fluid accumulation until the protein loss is decreased. If the circulating blood decreases in volume or if renal failure is suspected, intravenous fluid therapy may be required. 

If the albumin level decreases below a certain level, anticoagulant therapy is usually prescribed, most commonly with aspirin. Low dose aspirin therapy can also control thromboembolism, or when a blood clot blocks a blood vessel.

HMG-CoA reductase inhibitors, or statins, may be prescribed to lower cholesterol levels to help reduce hyperlipidemia. Generally, no other lipid-lowering drugs are recommended, but your veterinarian may put your dog on a diet specifically formulated for renal conditions that contain modified polyunsaturated fatty acid levels.

Chronic renal failure occurs in 70% of glomerulonephritis, and could cause the treatment to fail. Other reasons therapy may fail to yield positive results include a progression of amyloidosis, failure to identify or treat any underlying cancer or inflammatory disease, or if a fatal thromboembolism occurs.

The rate of recovery for amyloidosis is poor. If the nephrotic syndrome developed due to glomerulonephritis, recovery rates can vary, seeing some dogs recover spontaneously, while in others the disease progresses. If the underlying cause leading to the conditions that created the nephrotic syndrome is treated, leaving little permanent damage, the rate of recovery is much better. Therapy and recovery may also be affected by the high cost involved with the diagnosis and treatment of kidney diseases, and the lack of any specific therapy needed for the underlying cause. 

If the treatment is succeeding, you should see weight gain, a decrease in any swellings, and a decreased amount of protein loss. You will most likely visit your veterinarian often to monitor your dog and adjust treatments as needed.