A to Z Health Guide

Childhood Nephrotic Syndrome

What is childhood nephrotic syndrome?

Children with too much protein in their urine, sudden weight gain, and swelling in various body parts could have a condition called nephrotic syndrome. Childhood nephrotic syndrome is also called nephrosis.  Nephrotic syndrome happens when tiny structures in the kidneys called glomeruli stop working properly and let too much protein enter the kidneys.

What causes childhood nephrotic syndrome?
In most cases, the cause is not known. However, a number of conditions can damage the glomeruli and cause nephrotic syndrome. In children, the most common cause is due to minimal change disease. The cause of minimal change disease isn't known, but it can be related to infections, tumors, allergic reactions, and overuse of over-the-counter medications like ibuprofen and acetaminophen. Most children outgrow minimal change disease by the time they are in their teens.

Other conditions can damage the glomeruli, including other kidney conditions, immune system problems, infections, or diseases like cancer and diabetes. In certain cases, an allergic reaction to food or the use of certain legal and illegal drugs, or obesity can lead to nephrotic syndrome.

Do other kidney diseases cause swelling and protein in the urine?
Edema and protein in the urine are common in other types of kidney disease, especially glomerulonephritis.

Who gets it?
Usually, young children between the ages of 1 ½ and 5, although children of all ages and even adults can get it. It happens twice as often in boys than in girls.

How can I tell if my child has it?
You may see swelling around your child's eyes in the morning. Often, that's the first sign. As time passes, the swelling may last all day, and you may see swelling in your child's ankles, feet or belly. Also, your child may:

  • be more tired
  • be more irritable
  • have a decreased appetite
  • look pale.

Your child may have trouble putting on shoes or buttoning clothes because of swelling.

How is nephrotic syndrome diagnosed?
Your child's doctor will check for symptoms, such as swelling and pale skin. In addition, a urine test can check for the amount of protein, blood and other things to look for kidney damage. A blood test can show how well your child's kidneys are working. The doctor will also check for other diseases that may be causing the nephrotic syndrome. In some cases, diagnosis may also require a kidney biopsy.

How is the nephrotic syndrome treated?
Nephrotic syndrome is almost always treatable, but the treatment depends on the cause. The treatment's goal is to stop the loss of protein in the urine and increase the amount of urine passed from the body. Your doctor probably will prescribe a drug called prednisone for your child. Most children get better on this drug.

What does prednisone do?
Prednisone is a type of corticosteroid (also called "steroids"), which is used to stop the loss of protein from the blood. After one to four weeks of treatment, your child should begin urinating more often. As your child releases more urine, the swelling will go away.

What problems can occur with prednisone?
Prednisone can be a very effective drug, but it has a number of side effects. Some of these side effects can include:

  • increased hunger
  • weight gain
  • acne (pimples)
  • mood swings (very happy, then very sad)
  • over-activity or "hyper" behavior
  • a slowed growth rate
  • higher risk of infection.

Side effects are more common with larger doses and long-term use. Once prednisone is stopped (and only with the doctor's orders), most of these side effects disappear.

What if prednisone does not work?
If prednisone does not work for your child or if the side effects are too uncomfortable, the doctor may order another kind of medicine called an immunosuppressant. This drug decreases the activity of the body's immune system and is effective for most children. Your doctor can discuss in detail the good and bad aspects of immunosuppressants. The side effects of these drugs include increased susceptibility to infection, hair loss and decreased blood cell production.

Parents also should be aware that children taking immunosuppressive drugs may become ill if they are exposed to chickenpox. Therefore, you should notify your doctor immediately if your child is exposed to chickenpox while on these medications.

Your child might be given diuretics (water pills). Diuretics help the kidney rid the body of salt and water. The most common water pill for children is called furosemide.

What other problems happen with the nephrotic syndrome?
Most children will have problems only with swelling. However, a child with the nephrotic syndrome can develop a serious infection in the belly or blood clots in the legs. Both of these require immediate medical attention.

What can parents do?
Much of your child's care will be provided by you. Pay attention to your child's health, but do not overprotect your child. Your child needs to continue his or her usual activities, such as attending school and seeing friends. You should continue to treat your child like all other children in the family.

If your child is ill or taking prednisone, the doctor will recommend a low salt diet, which will minimize swelling. Your child will be allowed to drink as much he or she wants, however. The first sign that your child is getting sick again is the return of protein in the urine. Because of this, many doctors will ask that you check your child's urine regularly.

Does the disease ever go away?
Sometimes. Even though the nephrotic syndrome does not have a specific cure, the majority of children "outgrow" this disease in their late teens or in early adulthood. Some children will have only one attack of the syndrome. If your child does not have another attack for three years after the first one, chances are quite good that he or she will not get sick again.

Most children, however, often will have two or more attacks. The attacks are more frequent in the first two years after the syndrome strikes. After ten years, less than one child in five still suffers from attacks. Even if a child has numerous attacks, most will not develop permanent kidney damage. To prevent further attacks, the primary task of the caregiver is to control the accumulation of fluid in the child's body with prednisone and diuretics.

It is important to remember that children with this disease have an excellent long-term outlook and can live long, healthy lives.

If you would like more information, please contact us.

The information shared on our websites is information developed solely from internal experts on the subject matter, including medical advisory boards, who have developed guidelines for our patient content. This material does not constitute medical advice. It is intended for informational purposes only. No one associated with the National Kidney Foundation will answer medical questions via e-mail. Please consult a physician for specific treatment recommendations.