What is IgA Nephropathy?
IgA Nephropathy (also known as IgAN) is an autoimmune disease that affects the filters (glomeruli) of the kidneys. IgA is an immunoglobulin, which is a part of an individual’s healthy immune system. The IgA immunoglobulin normally attaches itself to an infection found in the body, triggering an immune response, and works to eliminate the infection. When an individual has IgA nephropathy, a defective form of IgA attaches itself to another IgA molecule instead of an infection, causing an immune complex. These then become stuck in the kidneys’ glomeruli, which damages the kidneys’ filters, causing blood and proteins to leak out of the kidneys and into the urine.
How is IgA Nephropathy diagnosed?
The presence of blood or protein in the urine through a routine urinalysis is usually the first step in diagnosing IgA Nephropathy. Blood test for serum creatinine can be used to calculate glomerular filtration rate (GFR), which reads how well your kidneys are filtering wastes from the blood. To confirm a diagnosis, however, it is necessary to do a kidney biopsy.
What are the symptoms of IgA Nephropathy?
IgA nephropathy usually doesn’t cause symptoms in the early stages. It is first suspected when routine urinalysis tests reveal protein and red blood cells in your urine that can’t be seen with the naked eye.
Symptoms of IgA nephropathy when kidney function is impaired include:
- Dark (cola or tea colored) urine caused by hematuria
- Proteinuria – Large amounts of protein “spilling” into the urine
- Edema – Swelling in parts of the body, most noticeable around the eyes, hands and feet, and abdomen.
- Low Blood Albumin Levels
- Foam in urine
- High Cholesterol in some cases
- High Blood Pressure in some cases
Who gets IgA Nephropathy?
Scientist have not found the cause of the defective IgA immunoglobulin in patients who suffer from IgA Nephropathy. It is likely to have both genetic and environmental components. IgA occurs mostly in Caucasian and Asians. It is uncommon in those of African decent. IgA is twice as common in males, and although it can affect any age group, it is usually diagnosed in young and middle-aged adults.
How is IgA Nephropathy treated?
There’s no cure for IgA nephropathy and no definitive way of knowing what course the disease will take. Some people experience complete remission, others live normal lives with low amounts of blood or protein in their urine, but some people progress to kidney failure.
Treatment with a number of medications can slow the progress of the disease and help manage symptoms such as high blood pressure, protein in the urine, and swelling.
It is important to see a kidney specialist on a regular basis to monitor kidney function, degree of proteinuria, cholesterol and blood pressure. Many different types of immunosuppressants, or drugs that suppress the immune system including steroids, can also be considered.
If remission is not obtained, it is important to be on a medication that reduces the amount of protein in the urine. These medications are called ACE-inhibitors (angiotensin converting enzyme inhibitors) and ARBs (angiotensin II receptor blockers).
Your nephrologist may also recommend:
- Diuretics to help eliminate excess fluids in the body
- Low-sodium diet help to control edema
- Anticoagulants to prevent blood clots
- Blood pressure medications to lower high blood pressure
- Statins to lower the cholesterol level
- Maintaining a healthy diet: Correct amounts of protein and fluid intake according to your nephrologist’s recommendations. A healthy diet consists of low salt with emphasis on fruits and vegetables low in saturated fat and cholesterol.
- Not smoking
The ultimate goal with treatment is to avoid progression into end stage kidney disease, which leads to the need for dialysis or kidney transplantation.
Interested in learning more about IgAN?
In this installment of our NephCure U educational program series, Drs. Barbara Gillespie and Patrick Nachman discuss how IgAN presents in patients, available treatment options, and clinical trial opportunities.