Uric Acid Test

Gout has the same symptoms as other types of arthritis including pseudogout, rheumatoid arthritis and osteoarthritis. The symptoms of high uric acid include joint inflammation and pain. The only way to determine gout decisively is by conducting tests to determine the concentration of uric acid in the blood or its presence in the joints.

The goal of testing is therefore threefold: to identify gout with certainty, differentiate it from other types of arthritis and determine the cause of increased uric acid levels in the blood. There are primarily two types of tests conducted, laboratory and non-laboratory. Recently, home tests have become increasingly popular as well.

Laboratory Uric Acid Tests

Serum Uric Acid Test detects elevated uric acid levels in the blood. Uric acid is measured from blood collected from a vein. An alternative test is Urine Uric Acid Test where uric acid concentration from a 24 hour urine sample is determined. A uric acid level higher than 6mg/dL indicates hyperuricemia which could be an indication of gout.

Uric acid test is commonly ordered for diagnosis of gout but hyperuricemia does not necessarily result to gout as lots of people can have it and not develop joint inflammation and swelling associated with gout. In the long term management of gout, these uric acid tests are used to determine if a treatment for gout, diet or lifestyle changes are effective in lowering uric acid levels. These tests are also used to monitor uric acid levels for secondary gout resulting from certain medications to treat heart disease or from metabolic diseases like leukemia and lymphoma.

Synovial Fluid Analysis is by far the most conclusive test to ascertain gout. The test consists of extracting the fluid of an inflamed or painful joint and examining it in the microscope for presence of uric acid crystals. The presence of these needle-like uric acid crystals is conclusive of gout. This test does not only determine gout it is also useful in determining other joint-related diseases and disorders such as viral or bacterial infection (septic arthritis), pseudogout (from the presence of calcium crystals) and autoimmune joint conditions such as rheumatoid arthritis and osteoarthritis.

Basic Metabolic Panel may also be ordered to monitor kidney function. The high uric acid that can lead to gout is either caused by excessive production or inefficient removal by the kidneys. This test therefore is helpful in investigating the cause of hyperuricemia.

Complete Blood Count (CBC) is also ordered to determine abnormal amounts of white blood cells in the blood which is an indication of immune response to presence of bacteria and differentiates gout from septic arthritis.

Non-laboratory test consist of X-rays done on affected joints that can show uric acid crystal deposits and joint damage indicative of chronic gout.

Uric Acid Home Test

Home testing of uric acid levels may now be done using portable uric acid meters that are very similar in function to glucose meters for diabetes. The earliest meters available in the market were manufactured in the UK but so far none have gained FDA approval in the US.

Gout experts further caution that home testing are indicative values only and may be used for monitoring but should not replace proven and established tests conducted in the laboratory.