Why Do I Have IgA Nephropathy?
Even though it’s one of the most common kidney diseases, doctors don’t know why it happens. It most often appears in adolescence or younger adulthood. People usually find out they have it before their 40th birthday. But it can happen at any age.
Your risk of IgA nephropathy is greater if:
- You’re male
- You’re Asian or white
- IgA nephropathy or IgA vasculitis (a condition that inflames your small blood vessels and makes them leaky) runs in your family
Certain genes you carry may make you more likely to get this condition. But it might also happen if you’ve had certain respiratory or intestinal infections. It may be related to how your immune system responds to those infections.
How Is IgA Nephropathy Treated?
Right now, there’s no way to cure or stop IgA nephropathy, in part because it’s not clear exactly why it happens. But your doctor can try to slow it down to prevent or delay end-stage kidney disease (ESKD).
Treatment options include:
Blood pressure medicine. If you have IgA nephropathy and high blood pressure, medicine to lower your blood pressure may help keep kidney disease from getting worse. Your doctor may suggest angiotensin-converting enzyme (ACE) inhibitors or angiotensin receptor blockers (ARBs). You might also take beta-blockers, calcium channel blockers, or other medicines. Other medications that target and inhibit the endothelin system are also used in those at risk of rapid disease progression. You may need more than one medicine to control your blood pressure.
Endothelin and angiotensin II receptor antagonists. This medication lowers the amount of protein in your urine.
Diuretics. These medicines work by removing extra fluid from your blood. This is another way to lower blood pressure. You might take diuretics with other blood pressure meds.
Immune-suppressing medicine. The goal is to limit the immune system activity and inflammation that damage your kidneys. Treatment may include steroids or newer medications that act on parts of the immune system called the complement system. You’ll take these medicines only if your doctor thinks you’re at high risk of worsening kidney damage.
Atacicept-vymj (Trutakna). The FDA granted this medicine accelerated approval to reduce proteinuria in adults with primary IgA nephropathy who are at risk for disease progression. You inject it under the skin once a week. It blocks APRIL and BLyS, two proteins that help certain immune cells produce the harmful antibodies involved in IgA nephropathy. In an ongoing clinical trial, Trutakna reduced proteinuria by 42% compared with a placebo after 36 weeks. Continued approval may depend on results that confirm its clinical benefit.
Cholesterol-lowering medicine. Statins are a common medicine used to lower cholesterol.
Sodium-glucose cotransporter-2 (SGLT2) inhibitors. These drugs were first used to lower blood sugar in people with diabetes. But data from clinical trials showed slowing of disease progression in people with diabetic nephropathy, and the drugs appear to work in people with IgA nephropathy. They're used when the kidneys are damaged.
Lifestyle changes. Along with medicine, it may help to eat foods that are low in:
- Salt
- Saturated fat
- Cholesterol
- Protein
Some doctors also recommend omega-3 fatty acids, although studies on the use of this in people with IgA nephropathy are mixed. If your doctor suggests eating less of certain foods, you’ll want to make sure you’re still getting the nutrition you need. They can refer you to a nutritionist or dietitian for more help.
How Do I Know If My IgA Nephropathy Will Get Worse?
Risk factors for worsening disease include:
A higher amount of protein in your urine. One study found that kidney function worsened 24 times faster in people with more than 3 grams of protein in their urine per day. But the amount of protein in your urine alone can’t predict what will happen, since even lower levels of proteinuria were linked to an increased risk of end-stage kidney disease
High blood pressure. If your blood pressure is high at diagnosis, you’re at more risk for worsening disease.
A low glomerular filtration rate (GFR). This test measures how well your kidneys are working to filter your blood. Low GFR is linked to worsening kidney damage.
Your kidney biopsy results. Certain things your doctor sees in a sample of your kidney tissue may suggest your condition is more likely to get worse. This includes crescent formations and immune deposits that are signs of more severe inflammation.
Other risk factors. Smoking and other kidney diseases also increase your risk for worsening IgA nephropathy.
How Will My Doctor Determine My Risk?
Before you start therapy, your doctor will likely check your risk for progressive or worsening disease. They may use something called the International IgA Nephropathy Prediction Tool (IIAN-PT). It’s an online tool or mobile app that calculates your risk of having a 50% drop in kidney function or progression to ESKD over the next 5 years. This tool takes many things into account at the time you had a kidney biopsy, including:
- Your kidney function (estimated GFR)
- Your blood pressure
- The amount of protein in your urine
- Your age
- Your race or ethnicity
- Whether you’ve taken certain blood pressure-lowering medicines before
- Certain features your doctor sees in your biopsied kidney tissue
- Whether you’re already taking medicines to suppress your immune system
Questions for Your Doctor
To help you think through treatment and understand what to expect and watch for, some good questions to ask your doctor include:
- What tests do I need to have done? What will the results show?
- Do I need treatment? What sort?
- Is my IgA nephropathy likely to get worse?
- Are there other things I can do to help protect my kidneys from further damage?
- Should I manage other conditions I have differently?
- Should I change my diet? How?
- How often should I see you or another doctor to check my kidneys?
- What symptoms should I watch out for?
- Who should I call if I have new questions or concerns?
Show Sources
Photo Credit: Moment/Getty Images
SOURCES:
National Institute of Diabetes and Digestive and Kidney Diseases: “IgA Nephropathy.”
UpToDate: “IgA nephropathy: Treatment and prognosis.”
Mayo Clinic: “IgA Nephropathy (Berger’s disease).”
JAMA Internal Medicine: “Evaluating a New International Risk-Prediction Tool in IgA Nephropathy.”
National Kidney Foundation: “SGLT2 Inhibitors.”
