Membranous nephropathy

• What is Membranous nephropathy?

  Membranous nephropathy is an autoimmune disease in which the body’s immune system targets and attacks the glomeruli. The glomeruli become leaky, leading to abnormal loss of protein in the urine (proteinuria) and a decrease in the ability of the kidneys to filter waste products and excess fluid from the blood. 

  There are two main types of membranous nephropathy. Primary membranous nephropathy is a condition limited to the kidneys due to an autoimmune process. It is the most common form of membranous nephropathy. In contrast, secondary membranous nephropathy refers to cases of membranous nephropathy related to an underlying systemic disease or condition such as infections (such as hepatitis, parasitic infection, or others), cancer, drugs, toxin, or systemic auto-immune diseases (such as lupus).  

  
  

• Who is at risk for Membranous Nephropathy?

  Membranous nephropathy is among the most common causes of nephrotic syndrome among adults ages 40 to 60. Additionally, those experiencing certain types of infections, autoimmune diseases, cancers, or medications (such as non-steroidal anti-inflammatory medications) are more susceptible to being diagnosed with the condition. Although this condition is reported among children, it is relatively rare. 

  
  

• What are the signs and symptoms of Membranous Nephropathy?

  Signs and symptoms of membranous nephropathy may include:

  • Foamy urine due to protein in the  urine 

  • Swelling (edema) throughout the body, including legs and face 

  • Weight gain due to excess fluid in the body 

  • High blood cholesterol 

  • High blood pressure (hypertension)

  • Blood clots (mainly associated with severe protein loss and very low levels of blood protein)

    
    

• What tests will my doctor perform to diagnose Membranous Nephropathy?

  Membranous nephropathy is usually suspected based on the medical history, clinical examination, and blood and urine tests measuring fat and protein levels. A kidney biopsy is usually required to confirm the diagnosis. A kidney biopsy is a procedure where a doctor takes a small sample of kidney tissue using a needle and studies the sample under a microscope.

  
  

• Treatment of Membranous Nephropathy

  Treatment of membranous nephropathy includes supportive measures such as salt and fluid restriction and medications to control blood pressure and reduce protein losses in the urine. 

  In moderate to severe cases of primary membranous nephropathy, immunosuppressive drugs may reduce or diminish the disease activity in the kidneys.

  In cases of secondary membranous nephropathy, treatment is usually directed at the underlying cause. 

  Membranous nephropathy often increases the risk of blood clots, and in some cases, blood thinning medications (anti-coagulation) may be required. Your doctor will discuss this with you.

  Do see your healthcare provider regularly and follow your treatment plan to prevent further damage to the kidneys and maintain kidney function. It is also essential to manage any underlying conditions contributing to the development of membranous nephropathy.

  
  

• Will I develop kidney failure if I have Membranous Nephropathy?

  Primary membranous nephropathy may sometimes resolve on its own in mild to moderate cases. However, in many cases, treatment is needed to prevent further kidney damage and maintain kidney function. In more severe cases, the condition can lead to kidney failure, which may require a kidney transplant or dialysis. Kidney failure is defined as a significant reduction in the glomerular filtration rate (GFR), which measures the kidney's ability to filter waste products from the blood.

  Not all people with membranous nephropathy will develop kidney failure. The progression of the disease and the likelihood of developing kidney failure can vary depending on several factors, which include the underlying cause of the membranous nephropathy, the severity of protein losses in the urine, and the level of kidney function.See your doctor regularly if you have membranous nephropathy to monitor your kidney function.

  Your doctor will perform regular blood and urine tests that will help assess disease progression and will make adjustments to your treatment plan as required.

  
  

• Clinical trials for Membranous Nephropathy

  New treatments and therapies are being developed for kidney diseases. Ask your doctor if you want to participate in a clinical trial for membranous nephropathy. More information is available at: www.enrollmypatient.org 

Authors: 

Vineel Kumar, Touro University - California, US

Victoria Vera, University of California, Berkeley - California, USA