Testing and Diagnosis of IgA Nephropathy

IgA nephropathy is often found by accident, when a routine test shows blood or protein in the urine. Because the early disease can be silent, the path to a diagnosis usually starts with simple tests and ends with a kidney biopsy.^1-4

Your health history and physical exam

Your diagnosis usually begins with a conversation. Your doctor will ask about your symptoms, your health history, and your family history. During the physical exam, they will likely check your blood pressure and look for signs of swelling.^1,3

Urine tests

Urine tests are a key first step because IgA nephropathy causes the kidneys to leak blood and protein into the urine. Your doctor may order:³

• Urinalysis – to check for blood in your urine.
• Urine protein test – to check for protein or albumin in your urine.
• A 24-hour urine collection – to measure how much protein you lose over a full day.

Blood tests

Blood tests help show how well your kidneys are working. Your doctor may check:³

• Waste levels – High levels of waste in your blood can be a sign that your kidneys are not filtering well.
• Estimated glomerular filtration rate (eGFR) – a blood test that estimates how much blood your kidneys filter each minute
• Cholesterol and protein levels – which can be affected by kidney disease

The kidney biopsy

While urine and blood tests can point to IgA nephropathy, the only way to confirm it is with a kidney biopsy. This is an important point: No blood or urine test alone can prove you have IgA nephropathy.^3,4

During a biopsy, your doctor uses a needle to remove a tiny piece of kidney tissue. A specialist then looks at it under a microscope. The biopsy can:^1,3

• Confirm the diagnosis by showing IgA deposits in the glomeruli.
• Show how much damage has occurred.
• Help predict how the disease may affect your kidneys.
• Guide treatment decisions.
• Show if there is an active disease going on in the kidneys.

It is normal to feel anxious in the days after a biopsy while you wait for results. Your care team can explain what to expect and answer your questions.

What happens after diagnosis

Once IgA nephropathy is confirmed, your doctor will likely refer you to a nephrologist, a doctor who specializes in kidney disease. They will use your test results to plan your care and to track your kidneys over time with repeat urine and blood tests.³

Comparing your results over time helps your team see whether your kidney function is stable or changing, and whether your treatment is working. This is why keeping your follow-up appointments matters, even when you feel well.³

Talk to your doctor

If a test has shown blood or protein in your urine, talk with your doctor about next steps. Ask what each test measures and what the results mean for you. Getting a clear diagnosis is the first step toward a treatment plan that protects your kidneys.^3,4