If you think you might have gout, it is important to get tested and diagnosed by a doctor, so that you can get the treatment you need. The tests for gout are:
Synovial fluid test
Synovial fluid is a liquid found in your body’s joints. This test looks at whether you have urate crystals in the joint fluid, which could mean you have gout. This is considered the most accurate test for diagnosing gout.
A synovial fluid test only takes a few minutes to complete. You may first be given anesthesia, a medicine to numb the area, through a shot using a small needle. Once the area is numb, your doctor or nurse will place a larger needle in the affected joint, and take a sample of the fluid. If you have received anesthesia, you should not feel much pain.
Uric acid blood test
A blood test can check the level of uric acid in your blood. A high level of uric acid could mean you have gout.
- A uric acid level in the blood between 3.5 and 7.2 milligrams per deciliter (mg/dl) is considered normal for most people.
- When you have gout, doctors recommend your uric acid level stay below 6.0 mg/dl.
Uric acid blood tests should not be used alone when diagnosing gout. This is because some people with high uric acid will never get gout, and some people with low uric acid do get gout. Doctors use the results of other tests together with the uric acid test to confirm whether you have gout or not.
Uric acid urine test
A urine test can check the level of uric acid in your body. A high level of uric acid could mean you have gout. The urine sample should be taken over 24 hours.
- A uric acid level in the urine between 250 and 750 mg is considered normal for most people.
Like a uric acid blood test, a uric acid urine test will not be used alone when diagnosing gout. Instead, doctors use the results of other tests together with the uric acid test to confirm whether you have gout or not.
Your doctor may take an X-ray of your joint to make sure your joint pain is not being caused by an injury or something other than gout. If you have chronic gout, your doctor may suggest a joint X-ray to see if you have any joint damage caused by gout.
An ultrasound machine uses sound waves to create images of the muscles and joints inside your body. Your doctor may use an ultrasound to look for urate crystals or tophi in your joints.
Dual-energy CT (DECT) scan
A DECT scan uses two types of X-rays to take pictures of the inside of your body. A DECT scan can find urate crystals that other tests cannot. This test is useful when the other tests cannot tell for sure if you have gout.