What Is Uric Acid?

During digestion of foods or from the normal breakdown of some of the body's cells, chemicals called purines (PURE-eens) enter the bloodstream. As they break down, they make uric (YER-ik) acid. The kidneys filter most uric acid out of blood, which then leaves the body in urine, or pee. Some uric acid also leaves the body in poop.

Uric acid can build up when the body makes too much or doesn’t get rid of enough of it. Too much uric acid can also form crystals or kidney stones.

What Is a Uric Acid Test & Why Is it Done?

A uric acid test measures the amount of uric acid in the blood. 

Doctors may order the test if a child's body is breaking down cells too quickly or not getting rid of uric acid as well as it should. Some kids with leukemia or other types of cancer can have high levels of uric acid (hyperuricemia).

A uric acid test also can help doctors monitor kids who get chemotherapy or radiation treatment. These treatments can increase the amount of uric acid in the blood, so the test lets doctors watch the level and help prevent it from getting too high.

The uric acid blood test also may be ordered if kids show signs of kidney failure, like high blood pressure, swelling, and growth problems. 

Top Things to Know

• A uric acid test checks how much uric acid is in the blood.
• The test is often given to kids during cancer treatment or to those who may have kidney problems. 
• Kids may need to stop taking certain medicines and fast before the blood test. 
• Your doctor can explain what it means if uric acid levels are high or low.

How Can I Help My Child Prepare for a Blood Test?

To help kids get ready for a blood test, find out if they need to fast (not eat or drink) or should stop taking medicines before the test. Explain what to expect during the test. If your child is nervous about it, work together on ways to stay calm. Deep breathing or even imagining being in a place that makes your child feel safe and relaxed can help.

What Do Uric Acid Blood Test Results Mean?

Your doctor will explain what the results of the uric acid test mean for your child. A “normal” level of uric acid can vary based on things like age and gender. 

High Uric Acid Level

 An increased level of uric acid may be caused by things like:

• side effects of chemotherapy or radiation
• problems with the thyroid, kidneys, bone marrow, or heart
• genetic conditions
• diabetic ketoacidosis
• psoriasis (seh-RYE-eh-siss)
• lead poisoning
• extreme exercise
• obesity
• dehydration
• foods and drinks with a lot of purines, like red meat, alcohol, and fructose (a kind of carbohydrate)
• certain medicines

Low Uric Acid Level

It’s not common to have a low level of uric acid (hypouricemia), but it can happen due to things like:

• starvation
• certain metabolic disorders or kidney, liver, or hormone problems
• a diet that doesn’t include a lot of foods rich in purines
• some medicines

What Else Should I Know?

If you have questions about the uric acid test or what the results mean, talk to your doctor.