Uric Acid

Overview

Uric acid is a chemical created when the body breaks down substances called purines. Purines are nitrogen-containing compounds found in the cells of the body, including our DNA. They are also found in foods and drinks. These include liver, anchovies, mackerel, dried beans and peas and certain alcoholic drinks, primarily beer.

Most uric acid dissolves in the blood and travels to the kidneys. From there, it passes out in our urine. If too much uric acid is produced or not enough is excreted, 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. Excess uric acid can also be deposited in tissues such as the kidney, leading to kidney stones or kidney failure.

The accumulation of too much uric acid is due to either increased production, decreased elimination, or a combination of both. Elevated levels of uric acid can occur when there is an increase in cell death, as seen with some cancer therapies or, rarely, as an inherited tendency to overproduce uric acid. Decreased elimination of uric acid is often a result of impaired kidney function due to kidney disease.

What does the test result mean?

Higher than normal uric acid levels in the blood is called hyperuricemia and can be caused by the overproduction of uric acid in the body or the inability of the kidneys to adequately remove enough uric acid from the body.

Increased concentrations of uric acid can cause crystals to form in the joints, which can lead to the joint inflammation and pain characteristic of gout. Uric acid can also form crystals or kidney stones that can damage the kidneys.

Low levels of uric acid in the blood are seen much less commonly than high levels and are seldom considered cause for concern. Although low values can be associated with liver or kidney disease, Fanconi syndrome, exposure to toxic compounds, and rarely as the result of an inherited metabolic defect (Wilson disease), these conditions are typically identified by other tests and symptoms and not by an isolated low uric acid result.

What should you do to prevent it?

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. 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, rapid weight loss, stress, and strenuous exercise all raise uric acid levels.