Uric Acid - testing for

Uric Acid Formally known as: Uric Acid
At A Glance Why get tested? To detect high levels of uric acid, which could be a sign of the condition gout, or to monitor uric acid levels when undergoing chemotherapy or radiation treatment When to get tested? When monitoring certain chemotherapy or radiation therapies for cancer; when you have joint pain or other symptoms that your doctor suspects may be due to gout Sample required? A blood sample drawn from a vein in the arm The Test Sample What is being tested? Uric acid is produced by the breakdown of purines. Purines are chemicals that come from nucleic acids (DNA). They enter the circulation from digestion of foods or from normal breakdown and turnover of cells in the body. Most uric acid is removed by the kidneys and disposed of in the urine; the remainder is excreted in the feces. If too much uric acid is produced or not enough is excreted, it can accumulate. The presence of excess uric acid can cause the condition called gout – an inflammation that occurs in joints when crystals derived from uric acid form in the joint fluid. The most common reasons for accumulation of uric acid are an inherited tendency to overproduce uric acid or impaired kidney function that results in decreased ability to excrete uric acid. How is the sample collected for testing? A blood sample is obtained by inserting a needle into a vein in your arm. The Test How is it used? The uric acid test is used to learn whether the body might be breaking down cells too quickly or not getting rid of uric acid quickly enough. The test also is used to monitor levels of uric acid when a patient has had chemotherapy or radiation treatments. When is it ordered? The uric acid test is ordered when a doctor suspects high levels of uric acid. Some patients with high levels of uric acid have a disease called gout, which is an inherited disorder that affects purine breakdown. Patients with gout suffer from joint pain, most often in their toes but in other joints as well. The test also is ordered as a monitoring test when a patient has undergone chemotherapy or radiation, to learn whether uric acid levels are getting dangerously high. The test may also be ordered if a patient appears to have failing kidneys. Patients who have high uric acid levels are sometimes put on a drug regimen to help lower uric acid levels. What does the test result mean? Higher than normal uric acid levels mean that the body is not handling the breakdown of purines well. The doctor will have to learn whether the cause is the over-production of uric acid, or if the body is unable to clear away the uric acid. Increased concentrations of uric acid can cause crystals to form in the joints, which leads to the joint inflammation and pain characteristic of gout. Uric acid can also form crystals or kidney stones that can damage the kidneys. Is there anything else I should know? Many drugs can increase or decrease the level of uric acid. In particular, diuretic drugs like thiazide drugs can cause uric acid levels to go up. Aspirin (and other salicylates) have varying effects on uric acid. At low aspirin levels (as may occur in persons taking aspirin only occasionally), aspirin can increase blood uric acid. On the other hand, in high doses (as may be used to treat rheumatoid arthritis), aspirin actually lowers the concentration of uric acid. For people who have uric acid kidney stones or gout, foods that are high in purine content should be avoided, including organ meats (like liver and kidneys), sardines and anchovies. Alcohol also should be avoided, because it slows down the removal of uric acid from the body. Fasting, a starvation diet, and strenuous exercise all raise uric acid levels. Although the uric acid test cannot definitively diagnose gout, a test for monosodium urate in synovial fluid (joint fluid) can. Common Questions 1. If I have high levels of uric acid, can they be lowered easily or will I have to take drugs for the rest of my life? Depending on the condition that causes your high levels of uric acid, you may not need to take drugs. If you have a sudden attack caused by high uric acid, as with an attack of gout, your doctor may treat you with the drug colchicine and a nonsteroidal anti-inflammatory drug, such as aspirin or ibuprofen. This treatment usually is short-term. However, you may have to stay on a maintenance therapy for a few years, until your uric acid levels come under control. You may be given drugs that help to rid your system of uric acid salts, such as probenecid, or you may be given drugs that interfere with uric acid production, such as allopurinol. If you have had chemotherapy or radiation, you may have to take uric acid tests more often and possibly treat the condition over time. 2. What is gout? Gout is one of the most common forms of arthritis. A gout attack usually happens at night, and within 12 or so hours there may be severe pain and swelling in the joint. Gout usually affects only one or two joints at the same time, typically in the feet and ankles. It often occurs in the big toe, and people can notice it at night when their bedding rubs on their toe and causes extreme pain. Gout happens when crystals derived from uric acid accumulate in the joints. These crystals cause inflammation. Without treatment, an early attack of gout usually goes away in a week. It may be months or years until the next attack. As time goes on, more joints can become affected and the disease may cause disabilities or eventually cripple the patient, according to the American College of Rheumatology. That is why it is important to get treated right away if you think you may have gout. Your doctor will order a uric acid test and may have to take fluid from the joint through a needle to look for the microscopic crystals. 3. I heard women don’t get gout. Is that true? No. Gout affects mostly men, and it is very rare in women until after menopause, the time in life when a woman’s monthly period stops. Ask A Question If you still have a question about your test or need help interpreting the results of your test, you can visit the ASCLS web site to complete a lab testing information request form, and a certified clinical laboratory scientist will gladly help you! Your communication will be kept confidential. Go there now: http://www.ascls.org/labtesting/disclaimer.asp. Related Pages On This Site Conditions: Arthritis, Gout Elsewhere On The Web American College of Rheumatology: Gout National Institute of Arthritis and Musculoskeletal Diseases: Fast Facts About Gout

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