Membranous nephropathy
Membranous glomerulonephritis; Membranous GN; Extramembranous glomerulonephritis; Glomerulonephritis - membranous; MGN
Membranous nephropathy is a kidney disorder that leads to changes and inflammation of the structures inside the kidney that help filter wastes and fluids. The inflammation may lead to problems with kidney function.
Causes
Membranous nephropathy is caused by the thickening of a part of the glomerular basement membrane. The glomerular basement membrane is a part of the kidneys that helps filter waste and extra fluid from the blood. The exact reason for this thickening is not known.
The thickened glomerular membrane does not work normally. As a result, large amounts of protein are lost in the urine.
This condition is one of the most common causes of nephrotic syndrome . This is a group of symptoms that include protein in the urine, low blood protein level, high cholesterol levels, high triglyceride levels, and swelling. Membranous nephropathy may be a primary kidney disease, or it may be associated with other conditions.
Nephrotic syndrome
Nephrotic syndrome is a group of symptoms that include protein in the urine, low blood protein levels in the blood, high cholesterol levels, high tri...
The following increase your risk for this condition:
- Cancers, especially lung and colon cancer
-
Exposure to toxins, including gold and
mercury
Mercury
This article discusses poisoning from mercury. This article is for information only. Do NOT use it to treat or manage an actual poison exposure. If...
-
Infections, including
hepatitis B
,
malaria
, syphilis, and endocarditis
Hepatitis B
Hepatitis B is irritation and swelling (inflammation) of the liver due to infection with the hepatitis B virus (HBV). Other types of viral hepatitis ...
Malaria
Malaria is a parasitic disease that involves high fevers, shaking chills, flu-like symptoms, and anemia.
- Medicines, including penicillamine, trimethadione, and skin-lightening creams
-
Systemic lupus erythematosus
, rheumatoid arthritis, Graves disease, and other autoimmune disorders
Systemic lupus erythematosus
Systemic lupus erythematosus (SLE) is an autoimmune disease. In this disease, the body's immune system mistakenly attacks healthy tissue. It can af...
The disorder occurs at any age, but is more common after age 40.
Symptoms
Symptoms often begin slowly over time, and may include:
-
Edema
(swelling) in any area of the body
Edema
Swelling is the enlargement of organs, skin, or other body parts. It is caused by a buildup of fluid in the tissues. The extra fluid can lead to a ...
- Fatigue
- Foamy appearance of urine (due to large amounts of protein)
-
Poor appetite
Poor appetite
A decreased appetite is when your desire to eat is reduced. The medical term for a loss of appetite is anorexia.
-
Urination, excessive at night
Urination, excessive at night
Normally, the amount of urine your body produces decreases at night. This allows most people to sleep 6 to 8 hours without having to urinate. Some p...
-
Weight gain
Weight gain
Unintentional weight gain is when you gain weight without trying to do so and you are not eating or drinking more.
Exams and Tests
A physical exam may show swelling (edema).
A urinalysis may reveal a large amount of protein in the urine . There may also be some blood in the urine . The glomerular filtration rate (the "speed" at which the kidneys cleanse the blood) is often nearly normal.
Urinalysis
Urinalysis is the physical, chemical, and microscopic examination of urine. It involves a number of tests to detect and measure various compounds th...
Protein in the urine
The protein urine dipstick test measures the presence of proteins, such as albumin, in a urine sample. Albumin and protein can also be measured using...
Blood in the urine
Blood in your urine is called hematuria. The amount may be very small and only detected with urine tests or under a microscope. In other cases, the...
Other tests may be done to see how well the kidneys are working and how the body is adapting to the kidney problem. These include:
-
Albumin
- blood and urine
Albumin
Albumin is a protein made by the liver. A serum albumin test measures the amount of this protein in the clear liquid portion of the blood. Albumin c...
-
Blood urea nitrogen
(BUN)
Blood urea nitrogen
BUN stands for blood urea nitrogen. Urea nitrogen is what forms when protein breaks down. A test can be done to measure the amount of urea nitrogen ...
-
Creatinine - blood
Creatinine - blood
The creatinine blood test measures the level of creatinine in the blood. This test is done to see how well your kidneys are working. Creatinine can ...
-
Creatinine clearance
Creatinine clearance
The creatinine clearance test helps provide information about how well the kidneys are working. The test compares the creatinine level in urine with...
- Lipid panel
- Protein - blood and urine
A kidney biopsy confirms the diagnosis.
Kidney biopsy
A kidney biopsy is the removal of a small piece of kidney tissue for examination.
The following tests can help determine the cause of membranous nephropathy:
- Antinuclear antibodies test
- Anti-double-strand DNA, if the antinuclear antibodies test is positive
- Blood tests to check for hepatitis B, hepatitis C, and syphilis
- Complement levels
-
Cryoglobulin test
Cryoglobulin test
Cryoglobulins are abnormal antibody proteins. This article describes the blood test used to check for them. In the laboratory, cryoglobulins come ou...
Treatment
The goal of treatment is to reduce symptoms and slow the progression of the disease.
Controlling blood pressure is the most important way to delay kidney damage. The goal is to keep blood pressure at or below 130/80 mm Hg. Angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs) are the medicines most often used to lower blood pressure.
Corticosteroids and other drugs that suppress the immune system may be used.
High blood cholesterol and triglyceride levels should be treated to reduce the risk of atherosclerosis . However, a low-fat, low-cholesterol diet is often not as helpful for people with membranous nephropathy. Medicines to reduce cholesterol and triglyceride levels (most often statins) may be recommended.
High blood cholesterol
Cholesterol is a fat (also called a lipid) that your body needs to work properly. Too much bad cholesterol can increase your chance of getting heart...
Atherosclerosis
Hardening of the arteries, also called atherosclerosis, occurs when fat, cholesterol, and other substances build up in the walls of arteries. These ...
Triglyceride
The triglyceride level is a blood test to measure the amount of triglycerides in your blood. Triglycerides are a type of fat. Your body makes some t...
A low-salt diet may help with swelling in the hands and legs. Water pills (diuretics) may also help with this problem.
Low-protein diets may be helpful. A moderate-protein diet (1 gram [gm] of protein per kilogram [kg] of body weight per day) may be suggested.
Vitamin D may need to be replaced if nephrotic syndrome is long-term ( chronic ) and does not respond to therapy.
Vitamin D
Vitamin D is a fat-soluble vitamin. Fat-soluble vitamins are stored in the body's fatty tissue.
Chronic
Chronic refers to something that continues over an extended period of time. A chronic condition is usually long-lasting and does not easily or quick...
This disease increases the risk for blood clots in the lungs and legs. Blood thinners may be prescribed to prevent these complications.
Outlook (Prognosis)
The outlook varies, depending on the amount of protein loss. There may be symptom-free periods and occasional flare-ups. Sometimes, the condition goes away, with or without therapy.
Most people with this disease will have kidney damage and some people will develop end-stage renal disease .
Kidney damage
Injury to the kidney and ureter is damage to the organs of the upper urinary tract.
End-stage renal disease
End-stage kidney disease is the last stage of chronic kidney disease. This is when your kidneys can no longer support your body's needs. End-stage k...
Possible Complications
Complications that may result from this disease include:
-
Chronic renal failure
Chronic renal failure
Chronic kidney disease is the slow loss of kidney function over time. The main job of the kidneys is to remove wastes and excess water from the body...
-
Deep venous thrombosis
Deep venous thrombosis
Deep vein thrombosis (DVT) is a condition that occurs when a blood clot forms in a vein deep inside a part of the body. It mainly affects the large ...
-
End-stage renal disease
End-stage renal disease
End-stage kidney disease is the last stage of chronic kidney disease. This is when your kidneys can no longer support your body's needs. End-stage k...
-
Nephrotic syndrome
Nephrotic syndrome
Nephrotic syndrome is a group of symptoms that include protein in the urine, low blood protein levels in the blood, high cholesterol levels, high tri...
-
Pulmonary embolism
Pulmonary embolism
A pulmonary embolus is a blockage of an artery in the lungs. The most common cause of the blockage is a blood clot.
-
Renal vein thrombosis
Renal vein thrombosis
Renal vein thrombosis is a blood clot that develops in the vein that drains blood from the kidney.
When to Contact a Medical Professional
Call for an appointment with your health care provider if:
- You have symptoms of membranous nephropathy
- Your symptoms get worse or don't go away
- You develop new symptoms
-
You have
decreased urine output
Decreased urine output
Decreased urine output means that you produce less urine than normal. Most adults make at least 500 ml of urine in 24 hours (a little over 2 cups)....
Prevention
Quickly treating disorders and avoiding substances that can cause membranous nephropathy may reduce your risk.
References
Manoharon A, Schelling JR, Diamond M, Chung-Park M, Madaio M, Sedor JR. Immune and inflammatory glomerular diseases. In: Alpern RJ, Moe OW, Caplan MJ, eds. Seldin and Giebisch's The Kidney . 5th ed. Philadelphia, PA: Elsevier; 2013:chap 82.
Salant DJ, Cattran DC. Membranous nephropathy. In: Johnson RJ, Feehally J, Floege J, eds. Comprehensive Clinical Nephrology . 5th ed. Philadelphia, PA: Elsevier Saunders; 2015:chap 20.
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Kidney anatomy - illustration
The kidneys are responsible for removing wastes from the body, regulating electrolyte balance and blood pressure, and stimulating red blood cell production.
Kidney anatomy
illustration
Review Date: 9/22/2015
Reviewed By: Charles Silberberg, DO, private practice specializing in nephrology, affiliated with New York Medical College, Division of Nephrology, Valhalla, NY. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.