What is nephrotic syndrome?

Nephrotic syndrome is characterized by the following symptoms that result from changes that occur to the small, functional structures in the kidneys, such as:

• Very high levels of protein in the urine

• Low levels of protein in the blood (albumin) due to its loss in the urine

• Tissue swelling all over the body (edema) especially in the abdomen (ascites)

• High cholesterol levels in the blood

• Decrease in frequency of urination

• Weight gain from excess fluid

What are the different types of nephrotic syndrome?

The type of nephrotic syndrome that is most common in children is called idiopathic nephrotic syndrome. It accounts for about 90 percent of children with nephrotic syndrome. Idiopathic means that a disease occurs with no known cause. The most common type of idiopathic nephrotic syndrome is called minimal-change nephrotic syndrome (MCNS).

With MCNS, the child usually has relapses of the illness, but the disease can usually be managed and prognosis is good. In rare cases, a child may develop kidney failure that requires dialysis.

There is a rare nephrotic syndrome present early after birth called congenital nephrotic syndrome. Congenital nephrotic syndrome is inherited. Children with this type of nephrotic syndrome have more severe disease.

What are the symptoms of nephrotic syndrome?

The following are the most common symptoms of nephrotic syndrome. However, each child may experience symptoms differently. Symptoms may include:

• Fatigue and malaise

• Decreased appetite

• Weight gain and facial swelling

• Abdominal swelling or pain

• Foamy urine

• Fluid accumulation in the body spaces (edema)

The symptoms of nephrotic syndrome may resemble other conditions and medical problems. Always consult your child's doctor for a diagnosis.

How is nephrotic syndrome diagnosed?

In addition to a thorough physical examination and complete medical history, your child's doctor may recommend the following diagnostic tests:

• Urine tests. Tests to check for protein in the urine

• Blood tests. Tests to check the levels of cholesterol and a special blood protein called albumin

• Renal ultrasound. A noninvasive test in which a transducer is passed over the kidney producing sound waves which bounce off of the kidney, transmitting a picture of the organ on a video screen. The test is used to determine the size and shape of the kidney and to detect a mass, kidney stone, cyst, or other obstruction or abnormalities.

• Renal biopsy. A procedure where a small sample of tissue is taken from the kidney through a needle. The tissue is sent for special testing to determine the specific disease.

What is the treatment for nephrotic syndrome?

Specific treatment for nephrotic syndrome will be determined by your child's doctor based on:

• Your child's age, overall health, and medical history

• The extent of the disease

• Your child's tolerance for specific medications, procedures, or therapies

• Expectations for the course of the disease

• Your opinion or preference

During the initial episode of nephrotic syndrome, your child may require hospitalization. He or she may need to be monitored if the edema is severe or if he or she has blood pressure and/or breathing problems.

Medications may be required to treat initial symptoms and during relapses. These medications may include:

• Corticosteroids

• Immunosuppressive drug therapy

• Diuretics (to reduce the edema)

• Intravenous (IV) albumin. A blood protein that can be administered to replace the low levels

• A special diet that restricts salt and has other specifications

The medications used to treat nephrotic syndrome weaken the immune system so your child should not receive live vaccines. If your child has been exposed to chickenpox and has not already had the vaccine, the vaccine may be recommended.

What is the long-term outlook for nephrotic syndrome?

Typically, relapses do occur throughout childhood. However, once a child reaches puberty, the disease usually stays in remission (complete or partial absence of symptoms). It is uncommon for symptoms to return during adulthood; however, it is possible.

Reviewed by: Division of Urology
Date: Nov. 2018