About the Test
Purpose of the test
The purpose of the test is to detect high levels of uric acid in the blood, which could be a sign of the condition gout, or to monitor uric acid levels when undergoing chemotherapy or radiation treatment for cancer. It is also used to detect high levels of uric acid in the urine to diagnose the cause of kidney stones and to monitor those with gout who are at risk of developing such stones.
What does the test measure?
The breakdown of purines — nitrogen-containing compounds found in the body’s cells, including our DNA — produces uric acid. This test measures the level of uric acid in the blood or urine.
As cells age and die, they break down, releasing purines into the blood. Various cancers with high cellular turnover can produce large amounts of uric acid (for example, chronic myeloid leukemia). To a lesser extent, purines may come from the digestion of certain foods, such as liver, anchovies, mackerel, dried beans and peas, and certain alcoholic drinks (primarily beer). Most uric acid is removed from the body by the kidneys and is eliminated from the body in the urine, with the remainder eliminated in the stool.
If too much uric acid is produced or not enough is removed, it can accumulate in the body, causing increased levels in the blood (hyperuricemia). The presence of excess uric acid can cause gout, a condition characterized by inflammation of the joints due to the formation of uric acid crystals in the joint (synovial) fluid. Uric acid crystals can be seen by examining joint fluid under a microscope. Excess uric acid can also be deposited in tissues such as the kidney, leading to kidney stones or kidney failure.
The build-up of too much uric acid in the body can be due to producing too much, not eliminating enough, or a combination of both. Elevated uric acid levels can occur when there is an increase in cell death, as seen with some cancer therapies or, rarely, as an inherited tendency to produce too much uric acid. Decreased elimination of uric acid is often a result of impaired kidney function due to kidney disease.
When should I get this test?
The uric acid blood test is ordered when a health care practitioner suspects someone has a high level of uric acid. Some people with high uric acid levels have a disease called gout, a common form of arthritis. People with gout suffer from joint pain, most often in their toes and other joints. The test is also ordered when cancer patients undergo chemotherapy or radiation therapy to ensure that uric acid levels are not dangerously high.
A urine uric acid test may be ordered when you suffer from recurrent kidney stones or have gout and need to be monitored for the formation of these stones.
Finding a Uric Acid Test
How can I get a uric acid test?
Uric acid testing is usually performed at a doctor’s office or another medical setting like a hospital or lab. These tests are normally requested by a doctor but may be available without orders from your doctor at a walk-in lab.
Can I take the test at home?
Uric acid at-home test kits are available but not common. At-home test kits usually use a blood sample from a finger prick to measure the amount of uric acid in the blood.
How much does the test cost?
The cost of a uric acid test will vary depending on factors such as where the test is done and whether you have health insurance. When ordered by a doctor, insurance typically covers the test, although you may have to pay a copay or deductible. Your doctor’s office, lab, and health plan can provide information about any out-of-pocket costs that may be your responsibility.
Taking a Uric Acid Test
The uric acid test usually requires a blood sample, which is usually taken from your arm in a doctor’s office, health clinic, hospital, or lab. However, in some cases, a sample of 24-hour urine collection may be used instead.
Before the test
Usually, no special preparation is required for a Uric Acid test.
During the test
A blood sample is taken from a vein in your arm. The person taking the sample may tie a band around your upper arm and will clean the area where the needle will be inserted into your skin. A small amount of blood is drawn into a tube. You may feel a slight sting when the needle enters your skin.
The process of taking a blood sample usually takes less than three minutes.
After the test
At a doctor’s office or lab, you will be asked to apply gentle pressure to the site with a bandage or a piece of gauze after the needle is withdrawn. This will help stop bleeding and may prevent bruising. Next, the site will be bandaged. You may resume your normal activities following the test.
A blood draw is a very low-risk procedure. You may have slight bruising at the site where the blood sample was taken.
Uric Acid Test Results
Receiving test results
The doctor who ordered your uric acid test may share the results with you, or you may be able to access them through an online patient portal. Uric acid results are usually available within a few business days.
Interpreting test results
Hyperuricemia, higher than normal uric acid levels in the blood, can be caused by producing too much uric acid or the inability of the kidneys to adequately remove enough of it from the body. Further investigation is needed to determine the cause of the overproduction or decreased elimination of uric acid.
The American College of Rheumatology published guidelines on the management of gout in 2012 that recommend that target uric acid levels should be below 6 mg/dL if you are diagnosed with the condition.
In the blood, low uric acid levels are seen much less commonly than high levels and are seldom considered a cause for concern. Low values can be associated with some kinds of liver or kidney diseases (for example, syndrome of inappropriate antidiuretic hormone or SIADH), Fanconi syndrome, and exposure to toxic compounds, low-purine diet, certain medications (for example, allopurinol, high-dose aspirin), and rarely as the result of an inherited metabolic defect (e.g., Wilson’s disease). But these conditions are typically identified by other tests and symptoms and not by an isolated low uric acid result.
High uric acid levels in the urine are seen with gout, multiple myeloma, metastatic cancer, leukemia, and a diet high in purines. Those at risk of kidney stones with high uric acid levels in their urine may be given medication to prevent stone formation.
Low urine uric acid levels may be seen with certain kidney disease, chronic alcohol use, and lead poisoning.
You may want to ask your doctor the following questions:
- Are there any common medications I should stop taking to control my uric acid level?
- Are there foods I should be avoiding?
- Am I at risk of getting gout?