What is nephrotic syndrome?
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.
What causes it?
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.
What are the symptoms?
Symptoms may include:
- Swelling around the eyes or in the feet or ankles. This is the most common symptom.
- Weight gain (from fluid buildup).
- Foam when urinating.
- Loss of appetite.
How is it diagnosed?
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.
How is nephrotic syndrome treated?
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.
How can you care for yourself?
Work with your doctor
- If your doctor prescribed medicines, take them as prescribed, even after you start to feel better. Call your doctor if you think you are having a problem with your medicine.
- See your doctor regularly to have your kidney function checked.
- Make sure your doctor knows about all the medicines, vitamins, or herbal supplements you take. This means anything you take with or without a prescription.
- Stay up to date on your COVID-19 vaccines. Get a flu shot each year. And get any other shots your doctor suggests.
Care for yourself at home
- Cut down on salt. This can reduce the amount of water your body retains.
- Follow your doctor's advice for the amounts of protein and potassium you need in your diet.
- Having nephrotic syndrome increases your risk for infections like peritonitis or respiratory and skin infections. Here are some tips to stay healthy:
- Wash your hands often, especially before eating and after being in public places.
- Avoid people who are sick.
- Use mild soaps, such as Dove or Cetaphil.
- Use moisturizing lotion after you bathe. You can use it more often if your skin is dry. Choose a lotion with no alcohol.
Current as of: May 4, 2022
Author: Healthwise Staff
E. Gregory Thompson MD - Internal Medicine
Adam Husney MD - Family Medicine
Kathleen Romito MD - Family Medicine
Tushar J. Vachharajani MD, FASN, FACP - Nephrology