Membranous Nephropathy – Causes, Symptoms, Diagnosis, & Treatment
What is membranous nephropathy?
Membranous nephropathy is a progressive kidney disease that affects glomerular basement membrane. Glomerular basement membrane inside the kidney consists of tiny filtering units that help filter wastes and fluids. This disease can lead to kidney failure over time. This disease can occur at any age but is more common after age 40.
What causes membranous nephropathy?
Membranous nephropathy is caused by inflammation of the glomerular basement membrane. The glomerular basement membrane helps filter waste and extra fluid from the blood. The exact reason for this inflammation is not known. When the inflamed glomerular membrane does not work normally, large amounts of proteins are lost in the urine.
Membranous nephropathy can occur as a primary kidney disease, or it may occur due to other conditions.
The following conditions increase your risk for this membranous nephropathy:
- Autoimmune diseases, such as systemic lupus erythematosus, rheumatoid arthritis, and Graves’ disease
- Cancers, particularly lung and colon cancer
- Exposure to gold and mercury and other toxins
- Infections, such as hepatitis B, malaria, syphilis, and endocarditis
- Medications, such as penicillamine, trimethadione, and skin-lightening creams
What are the symptoms of membranous nephropathy?
Symptoms of membranous nephropathy mostly show up slowly over time. The following symptoms may occur:
- Excessive urination at night
- Foamy appearance of urine
- Swelling in any area of the body
- Poor appetite
- Weight gain
How is membranous nephropathy diagnosed?
Your doctor will perform a physical exam and review your symptoms. The doctor may find edema (swelling) during the physical exam.
The doctor may do a urinalysis to check the amount of protein in the urine. He/she may find a large amount of protein and some blood in the urine.
The doctor may do some of the following tests to check the functioning of the kidneys:
- Blood and urine albumin
- Blood and urine protein
- Blood creatinine
- Creatinine clearance
- BUN (blood urea nitrogen)
- Lipid panel
The doctor may do a kidney biopsy to confirm the diagnosis.
The doctor may also do the following tests to find out the cause of the condition:
- Antinuclear antibodies test
- Anti-double-strand DNA (done only if the antinuclear antibodies test is positive)
- Blood tests to check for hepatitis B, hepatitis C, and syphilis
- Cryoglobulin test
- Complement levels
How is membranous nephropathy treated?
The goal of treatment is to improve symptoms and slow the progression of the disease. Your doctor may try and control blood pressure to delay kidney damage. The doctor may also treat high blood cholesterol and triglyceride levels to reduce the risk of atherosclerosis.
Your doctor may treat the condition with the following medicines:
- Angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs) to lower blood pressure
- Corticosteroids and other medicines to suppress the immune system
- Medicines (mostly statins) to lower cholesterol and triglyceride levels
- Diuretics (water pills) to decrease swelling
- Blood thinners to lower the risk of blood clots in the lungs and legs
This feature is for informational purposes only and is not intended to substitute the expert guidance of a doctor. We advise seeing a doctor if you have any health concerns.