Understanding Your Lab Results

Table of Contents

Introduction

It can be scary and unsettling to know that your kidneys are being damaged. Thankfully, routine urine and blood tests can give you and your healthcare team a clearer picture of the following:

  1. How your kidneys are working to filter your blood and
  2. How much protein is leaking into your urine (called proteinuria)? For some people, changes in these numbers can sometimes be seen before you feel any symptoms.

Lab results can help you and your healthcare team:

  • Monitor lab values for kidney function to look for changes (there can be ups and downs, so the key is to look at trends over time)
  • Determine the stage of your kidney disease on a scale of 1 to 5. 
  • Make adjustments to your treatment as needed
  • Check for specific health issues that can develop when the kidneys aren’t working correctly (for example, anemia, low levels of vitamin D, if there is a build-up of acid in the blood, as well as heart disease)

If you had a kidney biopsy, the findings also provide important information about your kidneys, including how much damage and inflammation are present.

Common tests used to monitor your lab values for kidney function

Below are three tests commonly used to monitor lab values for your kidney function.

GFR (glomerular filtration rate)

If you’re wondering what blood test shows kidney function, that would be a blood test to measure your GFR.

The creatinine is measured in the blood and the level is used in a mathematical formula, along with other personal factors, to calculate the GFR.

A GFR of 60 or higher is in the normal range.

A GFR below 60 may mean kidney disease.

A GFR of 15 or lower may mean kidney failure.

Creatinine levels go up in your blood when your kidneys are not working properly. So as creatinine goes up, GFR goes down. Your GFR also informs what stage of kidney disease you are in

Urine Tests

This is to look for protein or albumin in the urine (this is called proteinuria or albuminuria) or if blood spills into the urine (hematuria). These tests have many names, including a urinalysis, urine dipstick test, urine albumin, UACR, UPCR.  

When the kidneys are healthy, no protein is found in the urine. But with IgAN, protein can make its way into the urine. The less protein/albumin in your urine, the better. Albumin is a type of protein and may be measured rather than total protein. Lowering the amount of protein in your urine will be a key goal of your treatment plan.

blood pressure readings

Your doctor has likely told you how important it is to manage your blood pressure. That’s because high blood pressure and kidney disease often go hand-in-hand – and each makes the other worse. Keeping tabs on your blood pressure and taking steps to lower it is important for your kidneys.  

Click here for tips for lowering your blood pressure and taking your blood pressure correctly.

Learn More About BP

Your GFR or eGFR and the amount of protein in the urine can change. That’s why it is helpful to see trends over time.

Use our worksheet, Tracking Your Labs, Kidney Health and Blood Pressure, to write down your lab results. Always ask questions if you are unsure about what your lab results mean. Don’t forget to talk about how IgAN is affecting how you’re feeling and coping overall.

Video: Understanding Your IgA Labs

FAQs

What Blood test shows kidney function?

Blood tests commonly used to assess kidney function include:

  1. Creatinine Test: Measures creatinine level, a waste product from muscle metabolism. Elevated levels can indicate impaired kidney function.
  2. Blood Urea Nitrogen (BUN) Test: This test measures the amount of urea nitrogen in your blood, another waste product processed by the kidneys. Higher levels may suggest kidney issues.
  3. Glomerular Filtration Rate (GFR): Estimates how well your kidneys filter blood. A low GFR indicates decreased kidney function.
  4. Cystatin C Test: This test measures the level of cystatin C, a protein filtered by the kidneys. It can sometimes be used alongside creatinine to get a more accurate estimate of kidney function.

Together, These tests provide a good picture of how well the kidneys work.

How Do I Interpret IgA Test results?

The IgA test measures the Immunoglobulin A (IgA) level in your blood. IgA is an antibody that plays a critical role in the immune system, particularly in mucosal areas like the respiratory and gastrointestinal tracts.

IgA test results interpretation

Here’s a general guide for interpreting IgA test results:

Normal IgA Levels:
  • Normal ranges for IgA levels can vary slightly depending on the laboratory, but typical values are:
    • Adults: 70-400 mg/dL (milligrams per deciliter)
    • Children: Levels tend to be lower and gradually increase with age.
High IgA Levels:

Elevated IgA levels may indicate:

  • IgA Nephropathy: A kidney disease where IgA deposits build up in the kidneys, leading to inflammation.
  • Chronic Infections: Such as respiratory or gastrointestinal infections.
  • Autoimmune Diseases: Conditions like rheumatoid arthritis or lupus can cause elevated IgA levels.
  • Liver Diseases: Including cirrhosis or hepatitis.
  • Monoclonal Gammopathy: A condition that may lead to multiple myeloma or other blood disorders.
Low IgA Levels:

Decreased IgA levels may suggest:

  • Selective IgA Deficiency: A genetic condition where the body doesn’t produce enough IgA, which can lead to frequent infections.
  • Immunodeficiency Disorders: Conditions that affect the immune system, such as HIV.
  • Certain Medications or Treatments: Chemotherapy or immunosuppressive drugs can lower IgA levels.

It’s not always easy to know how quickly IgA Nephropathy might progress, but regular blood and urine tests and information from your kidney biopsy can help give clues as to how it might progress. Remember that everyone’s journey is different.