Appointments & care

At Mayo Clinic, we take the time to listen, to find answers and to provide you the best care.

Membranous nephropathy (MEM-bruh-nus nuh-FROP-uh-thee) occurs when the small blood vessels in the kidney (glomeruli), which filter wastes from the blood, become inflamed and thickened. As a result, proteins leak from the damaged blood vessels into the urine (proteinuria). For many, loss of these proteins eventually causes signs and symptoms known as nephrotic syndrome.

In mild cases, membranous nephropathy may get better on its own, without any treatment. As protein leakage increases, so does the risk of long-term kidney damage. In many, the disease ultimately leads to kidney failure. There's no absolute cure for membranous nephropathy, but successful treatment can lead to remission of proteinuria and a good long-term outlook.

Source: http://www.mayoclinic.com

Membranous nephropathy usually develops gradually, so you may not suspect that anything is wrong. As you lose protein from your blood, swelling in your legs and ankles and weight gain from excess fluid can occur. Some people experience lots of swelling from the very beginning of the disease, and others may not have any severe symptoms until they have advanced kidney disease.

Signs and symptoms of membranous nephropathy include:

• Swelling in the legs and ankles
• Weight gain
• Fatigue
• Poor appetite
• Frothy urine
• Elevated fat levels in the blood (hyperlipidemia)
• Increased protein levels in the urine (proteinuria)
• Decreased protein levels in the blood, particularly of the protein albumin

When to see a doctor

If you have blood in your urine, persistent swelling in your legs and ankles, or increased blood pressure, make an appointment to see a doctor.

Source: http://www.mayoclinic.com

In a majority of cases of membranous nephropathy, evidence of autoimmune activity can be found. Your body's immune system mistakes some of your own tissues as foreign and attacks them with autoantibodies. These autoantibodies can damage your kidney's filtering systems (glomeruli).

Sometimes membranous nephropathy is brought on by other causes, notably:

• Autoimmune disease, such as lupus erythematosus
• Infection with hepatitis B, hepatitis C or syphilis
• Certain medications, such as gold salts and nonsteroidal anti-inflammatory drugs
• Solid cancerous tumors or blood cancers

Membranous nephropathy may also occur along with other kidney diseases, such as diabetic nephropathy and rapidly progressive (crescentic) glomerulonephritis.

Source: http://www.mayoclinic.com

Appointments & care

At Mayo Clinic, we take the time to listen, to find answers and to provide you the best care.

To diagnose membranous nephropathy, your doctor may start with a detailed medical history and a physical exam. Your doctor may also recommend certain tests to identify possible causes and to determine how well your kidneys are working. These tests might include:

• Urine tests. You may be asked to provide a urine sample so that your doctor can determine the amount of protein present in your urine.
• Blood tests. From a sample of your blood, your doctor can test your cholesterol and triglyceride levels to see if they're elevated. Your doctor may also check your kidney function with a creatinine blood test. Fasting blood sugar and glycosylated hemoglobin tests check for diabetes. Other blood tests may reveal autoimmune diseases or infection with viruses, such as hepatitis B or hepatitis C.
• Glomerular filtration rate (GFR) test. The GFR test estimates your level of kidney function and can help your doctor determine your stage of kidney disease.
• Antinuclear antibody (ANA) test. The ANA test checks a sample of your blood for the presence of antinuclear antibodies, substances which attack your body's own tissues. High levels of antinuclear antibodies indicate an autoimmune disease.
• Imaging exam. An ultrasound or computerized tomography (CT) scan allows your doctor to see the structure of your kidneys and urinary tract.
• Kidney biopsy. In this procedure, your doctor removes a small piece of your kidney to examine under a microscope and identify what type of kidney disease you have. Kidney biopsy can also assess how much kidney damage has occurred and evaluate the effectiveness of treatment.

In some cases, membranous nephropathy occurs without any noticeable symptoms, and your doctor may discover the condition when the results of a routine urine test (urinalysis) show elevated protein levels in your urine (proteinuria).

Source: http://www.mayoclinic.com

Complications associated with membranous nephropathy include:

• High cholesterol. Levels of cholesterol and triglycerides are often high in people with membranous nephropathy, which greatly increases the risk of heart disease.
• Blood clots. With proteinuria, you may lose proteins that help prevent clotting from your blood into your urine. This makes you more prone to having blood clots develop in deep veins or blood clots that travel to your lungs.
• High blood pressure. Waste buildup in your blood (uremia) and salt retention can raise blood pressure.
• Infections. You're more susceptible to infections when proteinuria causes you to lose immune system proteins (antibodies) that protect you from infection.
• Nephrotic syndrome. High protein levels in the urine, low protein levels in the blood, high blood cholesterol, and swelling (edema) of the eyelids, feet and abdomen can lead to nephrotic syndrome — a cluster of signs and symptoms that affect your kidneys' filtering ability.
• Acute kidney failure. In cases of severe damage to the kidneys' filtering units (glomeruli), waste products may build up quickly in your blood. You may need emergency dialysis to remove extra fluids and waste from your blood.
• Chronic kidney disease. Your kidneys may gradually lose function over time to the point where you need dialysis or a kidney transplant.

Source: http://www.mayoclinic.com

Talk to your doctor about how to reduce your chances of developing kidney disease. Your doctor may suggest that you:

• Have regular checkups
• Follow your prescribed treatment for diabetes or high blood pressure
• Lose excess weight by following a healthy diet and regular exercise program
• Stop smoking, if you are a smoker
• Limit use of over-the-counter pain medications
• Make changes in your diet, such as eating less salt and less protein
• Limit your intake of alcohol

Source: http://www.mayoclinic.com

Factors that can increase your risk of membranous nephropathy include:

• Having a medical condition that can damage your kidneys. Certain diseases and conditions increase your risk of developing membranous nephropathy, such as lupus and other autoimmune diseases.
• Use of certain medications. Examples of medications that can cause membranous nephropathy include nonsteroidal anti-inflammatory drugs and gold salts.
• Exposure to certain infections. Examples of infections that increase the risk of membranous nephropathy include hepatitis B, hepatitis C and syphilis.
• Genetic background. Certain genetic factors make it more likely that you'll develop membranous nephropathy.

Source: http://www.mayoclinic.com