What is IgA Nephropathy?

Immunoglobulin A (IgA) nephropathy is a type of kidney disease. It is also called Berger’s disease. IgA nephropathy affects the glomeruli, which are tiny collections of blood vessels in the kidneys that help filter (clean) the blood.^1-3

What happens in IgA nephropathy?

Immunoglobulins like IgA are proteins made by the immune system. They play a role in fighting off infections and germs. Normally, the body tightly controls the process of making immunoglobulins. However, in people with IgA nephropathy, this is not the case. Instead, IgA builds up in places it should not be, like the kidneys.^1-4

Over time, this buildup leads to inflammation and damage to the blood vessels of the glomeruli. Once this happens, blood and protein can leak into the urine. As the kidneys get more damaged over time, other related health problems (complications) can arise. These include:^1,2,4

• High blood pressure
• High cholesterol in the blood
• Rapid (acute) kidney failure
• Heart problems
• Chronic, or long-term, kidney disease (CKD)
• Kidney failure

What causes IgA nephropathy?

It is not clear what causes IgA nephropathy. In some cases, IgA nephropathy can run in families. This suggests that there might be a genetic cause. IgA nephropathy can also occur along with some infections, like HIV.^1-4

People with celiac disease and liver diseases like cirrhosis are at higher risk for IgA nephropathy. Men are more likely to develop the condition than women.^1-4

Because of the possible genetic connection, experts think IgA nephropathy may be caused by a mix of problems. Some substance that triggers an immune response (antigen) must be present. This might be a virus, a bacteria, or something from inside the body’s own cells. People with a family history of IgA nephropathy might have genes that make it easier to get the disease but do not directly cause it.^1-4

What are the symptoms of IgA nephropathy?

While each person’s symptoms might be different, there are some common signs of IgA nephropathy. These are mostly related to the loss of blood, protein, and other important things in the urine due to kidney damage. Common symptoms include:^1-4

• Dark brown or tea-colored urine
• Blood in the urine (hematuria), which can be invisible to the eye
• Foamy urine (a sign of protein in the urine called proteinuria)
• Lower back or side pain
• Fatigue or weakness
• Swelling of the hands, feet, ankles, or face
• High blood pressure

Symptoms, especially changes in urine color, are often worse after an infection or exercise. If you notice any of these signs, talk to your doctor.³

How is IgA nephropathy diagnosed?

IgA nephropathy is most commonly diagnosed between the late teenage years and the late 30s. To diagnose it, your doctor will start by taking a full history of your symptoms and other health issues. They may ask about health issues in your family members, too. They will perform a physical exam, check your blood pressure, and run a few tests.^1-3

Most doctors will do a urine test (urinalysis) to look for signs of blood or proteins. They may also look at the level of cholesterol in your blood or markers of how well your kidneys are working. Some of these tests measure how well your kidneys work by using your creatinine (a waste product) levels and your glomerular filtration rate (GFR).^1-3

In some cases, you may need a kidney biopsy. This involves putting a small needle into your kidney and taking a sample of tissue. The sample can be looked at under a microscope to see what is going on within the glomeruli. In people with IgA nephropathy, there will be areas of IgA buildup.^1,2

How is IgA nephropathy treated?

Your doctor will decide what treatment you might need based on a few factors, including:⁵

• Severity of IgA buildup – This is determined by a biopsy.
• Amount of protein in your urine – Usually, amounts over 2,000 mg per day needs treatment.
• Creatinine clearance level – This blood test compares the amount of creatinine in your blood to the creatinine in your urine. Abnormal results (lower than normal creatinine clearance) occur in people with kidney problems like IgA nephropathy. If this is severe, treatment may be needed.

Treatment can slow down the progression of IgA nephropathy and help prevent CKD and kidney failure. Common medicines used to treat IgA nephropathy include:^1-3

• Blood pressure drugs – These include angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs).
• Diuretics – These are drugs that help the body get rid of extra fluid that is causing swelling.
• Immune system-suppressing drugs – Steroids and other immune system-suppressing drugs can help decrease inflammation and damage.
• Statins – These drugs help reduce cholesterol levels in the blood.

Other ways to manage IgA nephropathy may include:¹

• Decreasing salt, fat, and protein intake in your diet
• Safely limiting liquids
• Quitting smoking
• Exercising often
• Getting to and maintaining a healthy body weight

Chronic kidney disease and IgA nephropathy

As mentioned, IgA buildup and the damage it causes happen over time. They can go on for years before you know they are happening. But the damage can be serious and lead to CKD and permanent kidney problems.^1,2,4

Over time, CKD can lead to kidney failure. When a person enters kidney failure, they may need a kidney transplant or dialysis treatment. Dialysis helps filter the blood in the same way that healthy kidneys would.^2,3