Nephrotic syndrome (NS) comprises several rare kidney disorders and is an umbrella term used to describe a set of symptoms that occur when your kidneys aren’t functioning properly.      

Small blood vessels in your kidneys, called glomeruli, normally filter waste and excess fluids from your blood. When glomeruli become damaged, too much protein can leak from your blood into your urine.                                                 

Signs and symptoms of nephrotic syndrome                                                      

You may not discover that you have NS until you receive the results of routine blood and urine tests ordered by your doctor.                                                           

If you have NS, your lab results will usually show:                                                 

• Too much protein in your urine
• Too little of a protein called albumin in your blood, and
• Too much cholesterol in your blood.                                                             

There are also certain noticeable symptoms. These include:                                                         

• Swelling in your legs, feet, ankles, face, and/or hands,
• Weight gain,
• Constant fatigue,
• Foamy or bubbly urine, and
• Decrease in appetite.

Knowing what symptoms to look out for—and when to see your doctor—will help identify and treat the condition early and preserve kidney function.                                                         

Who is at risk for nephrotic syndrome?                                                        

Nephrotic syndrome is slightly more common in men than in women. In children, it is most common between the ages of two and six.                                

Certain factors and underlying diseases may increase your risk for developing NS, such as:                               

• Focal segmental glomerulosclerosis (FSGS),
• Minimal change disease (MCD),
• Membranous nephropathy,
• Lupus,
• Diabetes,
• Taking certain medicines, like nonsteroidal anti-inflammatory drugs (NSAIDs) or antibiotics, and
• Viral infections such as HIV, hepatitis B, hepatitis C, or malaria.

What causes nephrotic syndrome?                                                                  

In adults, the primary causes of nephrotic syndrome are rare kidney diseases, including membranous nephropathy and FSGS. FSGS involves the scarring or hardening of glomeruli and is diagnosed with a kidney biopsy. Most people with FSGS eventually experience kidney failure, requiring dialysis or a kidney transplant to extend life. Even after a transplant, FSGS can still return, leading to the loss of the newly transplanted organ.                                                           

In children, the most common cause of NS is MCD. This disease damages the kidneys’ tiny filters, called nephrons.                                                 

Secondary causes of NS involve diseases that affect the entire body, including diabetes and lupus. Diabetes is the most frequent secondary cause of NS in both adults and children.                  

Idiopathic nephrotic syndrome refers to nephrotic syndrome that occurs in the absence of an identifiable systemic cause.                                       

Learn more about Nephrotic Syndrome

Find out if you’re eligible to participate in a clinical trial for nephrotic syndrome!

How is nephrotic syndrome treated?                                                  

While there is currently no cure for NS, your doctor may prescribe medications and/or dietary modifications to treat your symptoms, prevent further damage to your kidneys, and avoid complications.                                       

Common complications of NS include:                                                    

● Blood clots,
● Infections, and
● Fatty buildup in veins and arteries, which increases the risk of a heart attack or stroke.            

Methods of managing NS often include:                                                              

• Medicine to control cholesterol,
• Corticosteroid medicines such as prednisone,
• Diuretic medications to help lower blood pressure and reduce swelling, and 
• Reducing your intake of protein, salt, and saturated fat.                              

If your kidneys stop working because of NS, you and your doctor will need to discuss the next steps, which may consist of dialysis, kidney transplantation, or palliative care.                                                     

Questions to ask your doctor about nephrotic syndrome                                                

If you’ve been recently diagnosed with nephrotic syndrome, here are some questions you may want to ask your healthcare provider.                                              

• What underlying problem is causing my symptoms?
• What can I do to manage my symptoms?
• What are the benefits and risks of each of these options?
• What can I do that might help slow the progression of NS?
• How much time do I have until I would need dialysis or a transplant?
• What is involved in both these choices?                                                       

Work closely with your healthcare team and family members to make informed decisions about your care.                                                        

Visit the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) website for more information on nephrotic syndrome in adults and nephrotic syndrome in children.                                                               

*American Kidney Fund (2022, December 5). Nephrotic syndrome treatments, causes & symptoms.  https://www.kidneyfund.org/kidney-disease/other-kidney-conditions/rare-diseases/nephrotic-syndrome/