What is nephrotic syndrome?

Healthy kidneys remove wastes from the blood. They also help balance water, salt, and mineral levels in the blood. Nephrotic syndrome is a sign that your child's kidneys aren't working right. When your child has this kidney problem, there will be high levels of protein in the urine. There may also be low levels of protein and high levels of cholesterol in the blood.

The most common symptom is swelling around the eyes or in the feet or ankles. Your child may also have foamy urine or weight gain from fluid buildup. The syndrome also increases the risk of infections.

The main cause of nephrotic syndrome in children is minimal change disease. In this disease, tiny blood vessels in the kidneys are damaged. They don't filter blood as they should. Nephrotic syndrome can also be caused by some infections and other diseases that affect the kidneys.

Which treatment your child gets depends on what is causing the syndrome. The doctor might prescribe medicines. Your child might also need other treatments if the syndrome is causing other health problems. These problems may include high or low blood pressure, or infections caused by bacteria.

Symptoms may include:

• Swelling around the eyes or in the feet or ankles. This is the most common symptom.
• Fatigue.
• Weight gain (from fluid buildup).
• Foam when urinating.
• Loss of appetite.

Treatment aims to reverse, slow, or prevent further kidney damage. The treatment you need depends on your age and what health problem is causing nephrotic syndrome.

Some people may not need medicine if they are at low risk for problems or are getting better on their own. Others may need medicines that decrease the body's immune system response. These include:

• Corticosteroids, such as prednisone.
• Other immune-suppressing medicines, such as cyclosporine and cyclophosphamide.

Nephrotic syndrome can lead to other problems that may need treatment, including high blood pressure, blood clots, and high cholesterol or triglycerides. You might need medicines to treat these problems, such as:

• Blood pressure medicines to lower blood pressure and help protect the kidneys.
• Water pills (diuretics). These help reduce fluid buildup in the body and lower blood pressure.
• Blood thinners to prevent blood clots.
• Statins to reduce high cholesterol.

Young children who get treatment usually get better and have no lasting problems. Often treatment is not as successful in older children and adults. If your symptoms are severe or they come back, you may need treatment for months to years, or even for the rest of your life.

If treatment doesn't stop the kidney damage, you may develop chronic kidney disease.

Doctors diagnose nephrotic syndrome using:

• Urine tests to measure the amount of protein in your urine.
• Blood tests to measure the amount of protein and cholesterol in your blood.
• A kidney biopsy.

You may also have other tests to identify what is causing nephrotic syndrome.

Work with your doctor

• If your doctor prescribed medicines, give them as prescribed. Keep giving them even after your child starts to feel better. Call your doctor if you think your child is having a problem with a medicine.
• See the doctor regularly to have your child's kidney function checked.
• Make sure your doctor knows about all the medicines, vitamins, or herbal supplements your child takes. This means anything your child takes with or without a prescription.
• Make sure your child gets a flu shot each year. Your child should also get any other shots your doctor suggests.

Care for your child at home

• Cut down on salt in your child's food. This can reduce the amount of water your child's body retains and can help treat the swelling.
• Follow your doctor's advice for the amounts of protein and potassium your child needs.
• Having nephrotic syndrome increases your child's risk for infections like peritonitis or respiratory and skin infections. Here are some tips to help your child stay healthy:
  • Wash your hands after changing diapers and before you touch food. Have your child wash their hands after using the toilet and before eating.
  • Avoid people who are sick.
  • Use mild soaps (such as Dove or Cetaphil).
  • Use moisturizing lotion after your child bathes. You can use it more often if the skin is dry. Choose a lotion with no alcohol.

Nephrotic syndrome is a sign that your kidneys aren't working right. As a result, you have:

• High levels of protein in your urine.
• Low levels of protein in your blood.

You may also have high levels of cholesterol in your blood.

Nephrotic syndrome isn't a disease. It's a warning that something is damaging your kidneys. Without treatment, that problem could cause kidney failure. So it's important to get treatment right away.

The kidneys have tiny blood vessels called glomeruli that filter waste and extra water from the blood. Healthy kidneys keep the right amount of protein in the blood. Protein helps move water from the tissues into the blood. When the tiny filters are damaged, too much protein slips from the blood into the urine. As a result, fluid builds up in the tissues and causes swelling.

Nephrotic syndrome is often caused by:

• A type of kidney disease called minimal change disease (or nil disease). This is the main cause of nephrotic syndrome in children. Doctors don't know what causes minimal change disease.
• Diabetes. This is the most common cause of nephrotic syndrome in adults.

Many other things can cause the blood vessel damage that leads to nephrotic syndrome, including:

• Kidney diseases that attack the glomeruli, such as membranous glomerulopathy and focal segmental glomerulosclerosis.
• Diseases such as lupus and certain cancers.
• Infections, such as HIV, hepatitis B, and hepatitis C.
• Medicines such as nonsteroidal anti-inflammatory drugs.

Sometimes doctors don't know what causes it.