uric acid in blood test

test overview

the blood uric acid test measures the amount of uric acid in a blood sample. uric acid is produced from the natural breakdown of your body's cells and from the foods you eat.

most of the uric acid is filtered out by the kidneys and passes out of the body in urine. a small amount passes out of the body in stool. but if too much uric acid is being produced or if the kidneys are not able to remove it from the blood normally, the level of uric acid in the blood increases.

high levels of uric acid in the blood can cause solid crystals to form within joints. this causes a painful condition called gout. if gout remains untreated, these uric acid crystals can build up in the joints and nearby tissues, forming hard lumpy deposits called tophi. high levels of uric acid may also cause kidney stones or kidney failure.

why it is done

a uric acid blood test is done to:

• help diagnose gout.
• check to see if kidney stones may be caused by high uric acid levels in the body.
• check to see if medicine that decreases uric acid levels is working.
• check uric acid levels in people who are undergoing chemotherapy or radiation therapy. these treatments destroy cancer cells that then may leak uric acid into the blood.

how to prepare

in general, there's nothing you have to do before this test, unless your doctor tells you to.

how it is done

a health professional uses a needle to take a blood sample, usually from the arm.

watch

how it feels

when a blood sample is taken, you may feel nothing at all from the needle. or you might feel a quick sting or pinch.

risks

there is very little chance of having a problem from this test. when a blood sample is taken, a small bruise may form at the site.

results

each lab has a different range for what's normal. your lab report should show the range that your lab uses for each test. the normal range is just a guide. your doctor will also look at your results based on your age, health, and other factors. a value that isn't in the normal range may still be normal for you.

many conditions can change uric acid levels. your doctor will talk with you about any abnormal results that may be related to your symptoms and past health.