Immunoglobulin A nephropathy (IgAN) is a type of kidney disease. It can lead to many serious health complications, including kidney failure and end-stage renal disease, life-threatening conditions that can only be treated with dialysis or kidney transplant.
Complications are more likely to occur when IgAN is untreated. There is no treatment that can cure IgAN, but there are therapies that can help slow progression, prevent complications, and keep the kidneys as healthy as possible. Treatment for IgAN is also improving, with several novel drug therapies that have become available in recent years.
How does IgAN damage the kidneys?
IgAN does not damage the kidneys directly. When a person has IgAN, the body produces abnormal versions of an antibody called immunoglobulin A (IgA). Normal versions of this antibody help fight infections in the respiratory system, digestive system, urinary system, and reproductive system.
The abnormal IgA produced when a person has IgAN form clumps of antibodies. Some of these clumps become stuck in the glomeruli, dense networks of blood vessels inside the kidneys that filter blood. This triggers an inflammatory response, as the body’s immune system attempts to break down and get rid of these deposits. This inflammatory response is what causes damage to the kidneys.
Over time, as this process occurs over and over, it can lead to a loss of kidney function, as healthy kidney tissue is replaced with scar tissue.
What causes IgAN?
It is not known why IgA nephropathy occurs in some people and not others. The condition is thought to be caused by a combination of genetic and environmental factors. In other words, a person’s genetics predispose them to having IgA nephropathy, and then the disease becomes active after being exposed to an environmental factor. One example of an environmental factor would be an infection.
Secondary IgAN
Sometimes IgAN occurs as a result of another health condition or a medication side effect. This is called secondary IgAN. Disorders associated with secondary IgAN include liver disease, autoimmune disorders, inflammatory bowel disease, psoriasis, and viral infections like hepatitis B, COVID-19, and HIV. Medications that change how the immune system works, blood thinners, and antithyroid medications have also been associated with secondary IgAN.
What medications treat IgAN?
The goals of treating IgAN are to get disease activity under control and prevent complications.
- Treatment usually includes medications that lower blood pressure and reduce protein in the urine (proteinuria). High blood pressure (hypertension) and proteinuria are common complications of IgAN. Hypertension and proteinuria can contribute to worsening kidney function, cardiovascular disease, and other problems.
- A healthcare provider may also prescribe a statin, a medication that helps lower the risk of cardiovascular disease by lowering cholesterol levels.
- Corticosteroids and other immunosuppressive drugs may also be prescribed at times. These medications dampen immune system activity and inflammation. This helps prevent further damage to the kidneys caused by inflammation.
- Mentioned above, several new drugs that treat IgAN have become available in recent years. Additional therapies are under development, and it is worth talking to a healthcare provider about newer treatment options and how they work.
Treatment for secondary IgAN can be different than treatment for IgAN that occurs on its own. Treatment for secondary IgAN will focus on addressing the condition, medication, or other underlying cause, and usually does not include treatment with immunosuppressive drugs.
Can lifestyle changes help manage IgAN?
IgAN cannot be treated with lifestyle changes alone, but lifestyle strategies can also play a role in managing the condition.
People with IgAN will need to limit the amount of sodium in their diet, and they may also be advised to lower their consumption of saturated fats and cholesterol. Anyone who smokes is strongly advised to quit smoking. Anyone who is overweight/obese should discuss weight loss with a healthcare provider.
Regular exercise can have many benefits to overall health, and people with IgAN should talk to a healthcare provider about what types of activity are recommended and any precautions that need to be taken.
Sources: Preeti Rout, Faten Limaiem, and Muhammad... + 9
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