Uric Acid Test
A uric acid test measures the levels of a waste product in your blood or urine to help diagnose conditions like gout or monitor kidney health.
What is a uric acid test?
This test measures the amount of uric acid in a sample of your blood or urine. Uric acid is a normal waste product that your body makes when it breaks down chemicals called purines. Purines come from your cells when they die and are also found in many foods and beverages.
Most uric acid dissolves in your blood. Your kidneys filter the uric acid out of your blood, and it leaves your body in your urine. If uric acid builds up in your blood, it can form needle-shaped crystals in and around your joints. This condition is called gout.
Gout is a type of arthritis that causes painful swelling in your joints. High uric acid levels can also cause kidney stones or kidney failure. But not everyone with high levels of uric acid will have these problems.
What is it used for?
A uric acid blood test may be used to:
- Help diagnose gout, usually when done with a synovial fluid analysis.
- Monitor uric acid levels in people who are having cancer chemotherapy or certain other cancer treatments.
A uric acid urine test may be used to:
- Help find out whether high levels of uric acid are causing kidney stones.
- Monitor the risk of developing kidney stones in people who have gout.
Why do I need a uric acid test?
You may need a uric acid blood test if you have symptoms of gout, which usually happen in one joint at a time (commonly the big toe, ankle, or knee), including:
- Intense pain
- Swelling
- Redness
- Feeling warm
You may also need a blood test if you have had or are having certain types of cancer treatments. You may need a urine test if you have symptoms of a kidney stone, such as sharp pain in your abdomen, side, or back, blood in your urine, or frequent urges to urinate.
What happens during a uric acid test?
For a blood test, a health care professional will take a blood sample from a vein in your arm. For a uric acid urine test, you will need to collect all your urine during a 24-hour period. You will be provided with a special container and instructions to store the urine in a refrigerator or cooler with ice throughout the collection period.
Will I need to do anything to prepare for the test?
Usually, you don't need any special preparations for a blood test. However, many medicines, including aspirin and niacin (vitamin B-3), can affect your results. Be sure to tell your provider about all the medicines you take, but do not stop taking them without consulting your provider first.
What do the results mean?
High uric acid levels in a blood test may be related to:
- Gout
- Kidney disease
- Leukemia, multiple myeloma, or metastatic cancer
- Side effects from cancer treatments
- Alcohol use disorder
- Preeclampsia
High uric levels in urine may be related to gout, kidney stones, certain cancers, obesity, or inherited genetic conditions like Lesch-Nyhan syndrome. If your results show high levels, it does not always mean you have a condition requiring treatment, as many people have high levels without health problems.