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Nephrotic Syndrome

Topic Overview

Picture of the urinary system

What is nephrotic syndrome?

Nephrotic syndrome is a sign that your Reference kidneys Opens New Window are not working right. You have nephrotic syndrome if you have high levels of protein in your urine, low levels of protein in the blood, and high cholesterol.

Nephrotic syndrome is not a disease. It is 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.

Nephrotic syndrome can occur at any age. But it is most common in children between the ages of 18 months and 8 years.

What causes nephrotic syndrome?

There are tiny blood vessels in the Reference kidneys Opens New Window Reference Opens New Window that filter waste and extra water from the blood. When these filters are damaged, you get nephrotic syndrome. Protein helps move water from the tissues into the blood. Healthy kidneys keep the right amount of protein in the blood. Damaged kidneys let protein slip from the blood into the urine. Without enough protein in the blood, fluid builds up in the tissues. This can cause swelling.

Many things can cause this blood vessel damage, including Reference diabetes Opens New Window, Reference lupus Opens New Window, infection, certain cancers, and some medicines. Sometimes doctors don't know what causes it.

A type of kidney disease called minimal change disease (also called nil disease) causes most of the cases of nephrotic syndrome in children. Doctors don't know what causes minimal change disease.

What are the symptoms?

The most common early symptom of nephrotic syndrome, in both children and adults, is swelling in the tissues around the eyes or in the feet or ankles. They may also have swelling in the lungs that can make it hard to breathe.

But many people who have nephrotic syndrome don't have symptoms.

How is nephrotic syndrome diagnosed?

Doctors diagnose nephrotic syndrome using blood and urine tests.

You may have other tests to see what is causing nephrotic syndrome. You may also have a kidney Reference biopsy Opens New Window, in which the doctor takes a sample of tissue for testing.

How is it treated?

Treatment focuses on reversing, slowing, or preventing further kidney damage. The treatment you need depends on whether you are an adult or a child and what health problem caused nephrotic syndrome. You may take medicine. And your doctor may suggest a diet that is low in salt and protein.

With treatment, young children usually get better and have no lasting problems. Often treatment is not as successful in older children and adults. If the kidney damage is not stopped, it can lead to Reference chronic kidney disease Opens New Window.

Frequently Asked Questions

Learning about nephrotic syndrome:	Reference What is nephrotic syndrome? Opens New Window Reference What causes it? Reference What are the symptoms? Reference What increases my risk for nephrotic syndrome?
Being diagnosed:	Reference Who can diagnose and treat nephrotic syndrome? Reference How will my doctor diagnose nephrotic syndrome? Reference Can it be prevented?
Getting treatment:	Reference How is nephrotic syndrome treated? Reference Will I need to take medicines? Reference Is surgery used to treat nephrotic syndrome?
Living with nephrotic syndrome:	Reference Reference How can I reduce my salt intake? Reference What can I do about my dry skin? Reference What medicines should I avoid if I have nephrotic syndrome?

By:	Reference Healthwise Staff	Last Revised: Reference May 7, 2012
Medical Review:	Reference Anne C. Poinier, MD - Internal Medicine Reference Tushar J. Vachharajani, MD, FASN, FACP - Nephrology

This information does not replace the advice of a doctor. Healthwise, Incorporated disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Reference Terms of Use. Reference How this information was developed to help you make better health decisions.