• Immunoglobulin A (IgA) nephropathy is a kidney disease that occurs when IgA antibodies become stuck in the kidneys, causing inflammation and damage.
• Common IgA nephropathy symptoms include blood and protein in the urine, swelling, and high blood pressure.
• Symptoms are most likely to occur in teenagers and adults under age 40.

IgA nephropathy — also known as Berger’s disease — is a kidney disease that develops when a specific type of antibody known as immunoglobulin A becomes stuck in the kidneys. These antibodies form immune complexes with other antibodies, making clumps that are too large to flow through the glomeruli (tiny filters) in the kidneys. This creates inflammation and damages the glomeruli, leading to several types of symptoms.

Knowing what symptoms to look out for in IgA nephropathy can help you recognize the disease and seek treatment sooner. If left untreated, IgA nephropathy can lead to chronic kidney disease and even end-stage renal disease (ESRD), causing permanent kidney damage.

Symptoms of IgA Nephropathy

IgA nephropathy can develop at any age, but it’s more common in teenagers and adults up to their late 30s. Asian and Caucasians are also more likely to have IgA nephropathy than other racial and ethnic groups, according to the National Institute of Diabetes and Digestive and Kidney Diseases.

Most people with IgA nephropathy don’t have any symptoms early in the disease. Over the course of several years to decades, the kidneys slowly become damaged, eventually causing noticeable symptoms. If you begin experiencing one or more of these symptoms, talk with your regular doctor or nephrologist (kidney specialist).

Blood in Urine

The most common first symptom of IgA nephropathy is hematuria (blood in the urine). Sometimes, hematuria shows up only in a urine test that is sensitive enough to detect a few blood cells. In other cases, the blood is immediately visible, turning urine pink or brown, similar to the color of cola or tea.

You may notice blood in your urine during or after a respiratory infection, such as a cold, or after vigorous exercise. When your body is fighting an infection, it makes more IgA to help destroy bacteria or viruses. As a result, more IgA antibodies form immune complexes and become stuck in your kidneys, causing symptoms.

Your kidneys are made of around 1 million nephrons — small structures that filter your blood. Each nephron has two parts, a glomerulus and a tubule. The glomerulus consists of tiny clusters of blood vessels with thin walls that filter out fluid, waste, and other small substances while leaving proteins and blood cells behind. However, when the glomeruli are damaged, blood cells can leak into the urine. Hematuria is a sign of damage to glomeruli in your kidneys.

Foamy Urine

Foamy urine may be a result of too much protein in your urine. This condition is known as proteinuria, and it’s another sign that IgA nephropathy may be damaging your kidneys. Proteins are important building blocks for bones and muscles, and they help your body repair itself. Specifically, the protein albumin may leak from the kidneys, so your doctor or nephrologist may refer to proteinuria as albuminuria.

When your kidneys filter your blood, the protein should stay in a blood vessel that runs alongside the glomeruli. Normally, proteins are too big to pass through the filter for excretion through your urine. However, in IgA nephropathy, these filters become damaged, allowing proteins to be excreted. This disease may also damage the kidneys’ tubules, which are responsible for collecting proteins to keep them in your body.

If you notice foamy urine along with other symptoms of IgA nephropathy, talk to your doctor or nephrologist. They can run a simple test using a dipstick that changes color based on the amount of protein in your urine.

Swollen Feet and Hands

As IgA nephropathy progresses, your kidneys become more damaged and can no longer function as well as they should. You may begin experiencing kidney disease symptoms and, in severe cases, end-stage kidney disease symptoms. One of these is edema (swelling).

Your kidneys help clear out extra fluid from your body in the form of urine. The tubules in your kidneys collect and return the substances your body needs back into your blood vessels, and the remaining fluid then becomes urine.

In people with IgA nephropathy, this filtering process is disrupted. Albumin is important for maintaining your body’s fluid balance — without this protein, your body loses its ability to reabsorb extra fluid. As a result, the extra fluid collects in your feet, ankles, and hands, causing swelling and shiny, tight-feeling skin.

Your health care provider may prescribe a diuretic to help your kidneys filter excess fluid. These medications also help control high blood pressure, another symptom of IgA nephropathy.

High Blood Pressure

Extra fluid in your body puts more stress on your blood vessels, causing your blood pressure to rise. High blood pressure caused by kidney disease often develops quickly and can be severe. If it’s not treated, high blood pressure can further damage your kidneys, leading to more severe symptoms and, eventually, chronic kidney disease.

Most people with high blood pressure don’t have any noticeable symptoms, so this condition can be difficult to catch. You may have headaches, shortness of breath, or nosebleeds, but these tend to occur only when blood pressure levels get dangerously high. Regular blood pressure screenings at doctors’ visits can help you monitor your blood pressure and keep it under control.

To help treat high blood pressure, your doctor or nephrologist may prescribe one of several blood pressure medications. These drugs can help relax your blood vessels, allowing blood to flow through them more easily.

Angiotensin converting enzyme inhibitors (ACE inhibitors) and angiotensin-receptor blockers (ARBs) are typically prescribed to treat high blood pressure and slow kidney disease progression. They can be prescribed along with diuretics to boost their effects.

Talk to Your Doctor About IgA Nephropathy

If you’ve noticed one or more symptoms of IgA nephropathy recently, make an appointment to talk to your doctor or nephrologist. They can run a series of tests to measure your kidney function and make a diagnosis. The sooner you begin treatment, the fewer complications you’re likely to have.

According to the National Kidney Foundation, tests for IgA nephropathy include:

• A physical exam to look for swelling and skin changes
• Urinalysis to check for blood and protein in your urine
• Blood tests to measure your glomerular filtration rate (GFR), which checks your kidney function
• A kidney biopsy (taking a small piece of kidney tissue to examine under a microscope) to look for IgA deposits

Depending on your symptoms, your doctor or nephrologist will fine-tune your treatment plan and may prescribe medications to:

• Treat high blood pressure
• Remove extra fluid from your body
• Dampen your immune system (using corticosteroids or immunosuppressive medications)
• Reduce high cholesterol levels (using statins)

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Do you have IgA nephropathy? What symptoms have you experienced? Share your story in the comments below.