What Is Membranoproliferative Glomerulonephritis?
Glomeruli are structures in the kidney that help to filter wastes from the blood. When these structures become inflamed, a condition known as glomerulonephritis (GN) develops. Membranoproliferative glomerulonephritis (MPGN) is a specific type of GN that occurs when the body’s immune system functions abnormally. The immune system, which is responsible for fighting disease, begins to attack healthy cells in the kidney, destroying the function of the glomeruli.
Although membranoproliferative glomerulonephritis is the common term used to describe this condition, MPGN goes by other names, including:
- mesangiocapillary glomerulonephritis
MPGN has two different subtypes: type I and type II. Most cases of the disorder are type I. Type II is much less common and is a more aggressive form of the disease.
What Causes Membranoproliferative Glomerulonephritis?
MPGN occurs when the body’s immune system malfunctions, attacking healthy cells. Underlying conditions that contribute to abnormal immune system function include:
- autoimmune diseases such as scleroderma, lupus, Sjogren’s syndrome, and sarcoidosis
- certain cancers such as leukemia and lymphoma
- certain types of infections such as hepatitis B, hepatitis C, malaria, and endocarditis
Sometimes it is not possible to identify the cause of the disease. MPGN typically develops in children between the ages of 8 and 16 who have one of these conditions.
What Are the Symptoms of Membranoproliferative Glomerulonephritis?
The symptoms of MPGN vary from person to person and will depend on the type of the disease that your child has. In some cases, individuals will not have any symptoms of disease. In others, damage to the kidney will produce specific symptoms commonly associated with kidney disease:
- blood in the urine
- changes in mental status including decreased alertness
- cloudy urine
- dark urine
- a decrease in urine volume
- swelling (edema) in the hands, feet, or face
How Is Membranoproliferative Glomerulonephritis Diagnosed?
To diagnose MPGN, your doctor will give you a physical exam and order blood and urine tests. If you have edema of the hands or feet and have high blood pressure, your doctor will order several different tests to confirm your diagnosis. Blood and urine tests used to diagnose MPGN include:
- blood urea nitrogen (BUN) and creatinine level tests
- serum complement C3 nephritic factor level test
- serum complement level test
- urine protein
If these results indicate the presence of MPGN, your doctor will also order a kidney biopsy. A kidney biopsy requires the removal of a small sample of tissue from your kidneys. Your doctor will need the results of this test to determine if you have MPGN type I or II.
How Is Membranoproliferative Glomerulonephritis Treated?
Treatment of MPGN depends on the severity of your condition. There is no cure for the disease. Treatment focuses on controlling symptoms and slowing the progression of the disease. Your doctor may ask you to change your diet. You may need to limit your intake of salt, protein, and fluids. Your doctor may also prescribe medications to control your blood pressure. Medications may also be ordered to suppress your immune system. Your doctor will be able to tailor your treatment to address your symptoms.
As the disease progresses, more damage to the kidney will occur. If kidney failure results, you may need dialysis to remove toxins from your blood. Dialysis will clean your blood when your kidneys are no longer able to do so. You may also undergo a kidney transplant if your kidneys fail.
What Complications Are Associated With Membranoproliferative Glomerulonephritis?
The most common complication of MPGN is acute or chronic nephritis. Nephritis is a group of symptoms associated with kidney disease including:
- blood in the urine
- decreased urine output
- blurred vision
- decreased alertness
- muscle aches and joint pain
- shortness of breath
High blood pressure may also develop. As the disease progresses, individuals will likely experience kidney failure.
What Is the Long-Term Outlook for Patients With Membranoproliferative Glomerulonephritis?
If you have MPGN, your long-term outlook will vary based on the severity of your disease and your overall health. You will need to talk to your doctor about what you can expect. In some cases, the disease may not progress for many years. Regular checkups will be needed to monitor your health. In other cases, MPGN may resolve without treatment.
Some patients will experience a rapid decline in their health. These patients will develop kidney failure and will require dialysis or a kidney transplant. Although a kidney transplant will alleviate the need for dialysis, it is common for individuals to experience a recurrence of MPGN following their organ transplant. So, a kidney transplant will not cure the disease.