IgA nephropathy (IgAN) is a disease that happens when an abnormal protein leads to an immune response that damages glomeruli. Those are the tiny filters in your kidneys. IgAN can lead to inflammation, scarring, and loss of kidney function.
To better understand IgAN and how to manage it, we spoke with Jeffrey Turner, MD, associate professor of medicine (nephrology) and clinical chief, Section of Nephrology, Internal Medicine at Yale School of Medicine in New Haven, Connecticut.
As a nephrologist, Turner treats many forms of kidney disease. He shares what he sees in clinic and what he wants people with IgA nephropathy to know.
Q: What affects someone’s outlook?
IgA nephropathy can have a wide range of trajectories. Some people have mild disease that stays mild. Others develop serious problems like kidney failure and the need for dialysis.
Your doctor can’t predict exactly what will happen, but there are ways to better understand whether your kidneys seem likely to stay stable for a long time or whether you’re in a group that needs a closer watch and stronger treatment.
One of the most important things we test early on is how much protein you’re spilling into your urine. We also look at how well your kidneys are working, usually with a blood test called creatinine. Creatinine is a waste product your kidneys normally filter from your blood. Too much creatinine in your blood can mean your kidneys aren’t working as they should.
There are other things we consider, but those two measures help us better understand what treatment you may need and how aggressive we should be.
Q: What are the early symptoms of IgAN?
Sometimes you may notice blood in your urine, especially around an infection. We call this hematuria.
But this is typically a disease that many people don’t know they have, not until you get routine blood or urine tests that show something isn’t right. That’s usually what leads to a deeper look at your kidney health.
Q: Why are regular follow-ups so important?
We can treat IgA nephropathy, and the disease can go into remission. But it’s a lifelong condition that can become active again months or years later without causing noticeable symptoms. Regular urine and blood tests help us catch a flare, hopefully before it causes more kidney damage.
How often you need testing depends on your specific situation. If you’re newly diagnosed, have more severe disease, or start a treatment that needs close tracking, you may need blood work several times a month.
We can usually spread out the visits and labs once things become stable. Even when your kidney function looks good, you should still expect lab work once or twice a year.
Q: How do you decide which medication to start with?
There are really two broad parts of drug treatment.
One part directly targets the immune process that’s damaging your kidneys. These treatments are more likely to come into the picture if you’re leaking a lot of protein into your urine or your kidney function is already reduced.
The other part is kidney protection. These are medicines we use for all different types of kidney disease. Certain blood pressure-lowering drugs and medicines like SGLT2 inhibitors can change pressure and blood flow inside the kidney in ways that help protect kidney function over months and years.
If your IgA nephropathy looks very mild, we may watch it closely without starting more aggressive treatment. We may still use kidney-protective medicines and suggest lifestyle changes.
But if there’s a lot of protein in your urine or more kidney damage, we’re more likely to immediately add treatment that directly targets the immune pathway that drives IgAN.
Q: Has treatment changed much in the last decade?
Yes. There’s been a lot of evolution in how we treat IgA nephropathy, and there are more drugs being studied in clinical trials.
For a long time, if you were at a high risk of progression, we relied on broader medicines that suppress the entire immune system, such as prednisone. Now we have several FDA-approved medications that target specific parts of the immune system involved in IgA nephropathy.
This is a very active area of research, and I expect we’ll keep seeing new options. Even five years from now, treatment options will probably look different.
Q: How do you decide how long to continue drug treatment?
As doctors, we’re very good at starting medications. We’re often much less certain about when to stop them, especially if they’re working well.
If you have a more aggressive form of IgAN and treatment puts you in remission, I’m more confident about having you stay on an effective treatment for many months, a year, or a couple of years. After that amount of time, it can become less clear when it’s safe to pull back.
I try to be open about that uncertainty. At each visit, we look again at your lab tests. What does your prognosis look like now? What are the risks of reducing or stopping a medicine compared with staying on it?
Your goals and preferences also matter. Some people feel strongly that they want to avoid a recurrence and are comfortable staying on treatment longer. Others are more concerned about medications or side effects and may want to stop earlier, even if that carries more risk.
In my experience, many of the medications we use for IgA nephropathy are well tolerated. But deciding how long you stay on them is a choice we make together, and you should feel like you’re part of the decision-making process.
Q: What lifestyle changes matter most for kidney protection?
Lifestyle changes aren’t a replacement for medication, especially if your disease is very active. But this is a chronic condition, and the choices you make every day become very important when you think about protecting your kidneys over five, 10, 15, or 20 years.
In general, a diet that’s healthy for your heart is also going to be healthy for your kidneys. I often suggest a Mediterranean-style diet, which is rich in fruits and vegetables but lower in sweets and high-fat foods.
Some people with less kidney function may need to be careful with high-potassium foods because their kidneys may have trouble getting rid of potassium. That’s something you should talk about with your doctor or a dietitian because it isn’t the same for everyone.
Salt is another big one. When the kidneys are injured, they can have a harder time getting rid of sodium. That raises blood pressure and can cause fluid retention and other problems, so a lower-salt diet is important.
Exercise is also key. We may not understand every detail of how it helps with IgA nephropathy specifically, but being active is good for your heart and blood vessels. Over many years, better blood flow can help protect your kidney function as well.
Q: Do people with IgAN need to drink extra water?
Not necessarily. I see people get the message that drinking more and more water will protect their kidneys, but there really can be too much of a good thing.
If you drink excessive amounts of water, your sodium level can drop too low — that’s called hyponatremia — and it can be dangerous. On the other hand, if you’re dehydrated, your kidneys don’t get the blood flow they need and can be harmed that way too.
There isn’t one perfect fluid number for everybody. How much you need changes with things like heat, activity, and how well your kidneys are working.
As a general ballpark, I often suggest around 2 liters of fluid a day. Some people with more impaired kidneys may need less than that. Someone spending a lot of time outside in hot weather and sweating may need more.
Q: What symptoms should you call your doctor about?
If you suddenly develop a lot of swelling in your legs or feet for no clear reason, that’s a reason to call your doctor. The same goes for a noticeable change in your urine, such as if it suddenly looks darker, tea-colored, or reddish from blood.
I also often urge people with IgA nephropathy to keep track of their blood pressure at home. If your blood pressure unexpectedly starts going up, that’s another reason to check in with your care team.
Q: Why do some people develop IgAN? Can you cause it?
With primary IgA nephropathy, the kind that isn’t linked to another condition, we still don’t know exactly why one person develops it and another doesn’t. For most people, it’s likely a mix of immune, genetic, and environmental factors that we’re still working to fully understand.
But IgAN isn’t your fault. I strongly discourage people from blaming themselves.
Q: Is IgAN inherited?
We don’t have evidence that IgA nephropathy is caused by a single gene that gets passed directly from parent to child. There are likely several genes that can slightly raise a person’s chance of developing it, but genetics alone don’t seem to explain who gets this disease.
From what we know now, there isn’t a strong or predictable inheritance pattern. I don’t tell people, “Because you have IgA nephropathy, your children are likely to get it.”
Q: Why is IgAN sometimes linked with other diseases?
IgA is a type of antibody that has an important role in protecting the lining of our mucosa (the part of our body that protects our insides from the outside), including the intestinal tract. A lot of IgA is made by immune cells in the gut.
Diseases such as celiac disease, ulcerative colitis, and Crohn’s disease all involve abnormal immune activity in the gut. The thinking is that when the immune system is highly active there, one possible consequence is the production of abnormal IgA antibodies that can then be involved in kidney disease.
That doesn’t happen to everyone with those conditions, but it helps explain why we see an association between IgA nephropathy and some diseases of the gut.
Liver disease and hepatitis infections are also associated with IgA nephropathy, likely through similar immune mechanisms. But it’s important to say that most people with IgA nephropathy don’t have one of these other conditions — they’re just groups we see more often than we would by chance.
Q: What are you most excited about in IgAN treatment?
We’re learning how to target the immune process involved in IgAN in much more specific ways.
Some of the newer treatments being studied affect a part of the immune system called complement, which helps trigger certain immune reactions. Other treatments target signaling molecules that activate B cells, which are immune cells involved in making antibodies.
What’s exciting is that these approaches may give us more effective treatments for IgA nephropathy with a more precise effect on the pathways that are actually driving the disease.
And because many immune pathways overlap across autoimmune diseases, what we learn may ultimately help us understand and treat other immune-related conditions.
Q: What should people with IgAN keep in mind?
You’re not alone. IgA nephropathy is one of the most common diseases that affects the kidney’s tiny filters. It’s becoming a more and more easily treatable disease.
The most important things are awareness, getting the right diagnosis, and staying on top of monitoring. Those steps can lead to very good outcomes. We already have more good treatments available now than we did even a few years ago, and there are more coming.
What you don’t want to do is ignore the disease because you feel fine and hope it goes away. It needs to be followed. But with regular checkups, lab work, and the treatments we have now, there’s a lot we can do to help protect your kidney health over time.