Synovial Fluid for Analysis with Uric Acid Crystals

Specimen Required

FLUID (All Body Fluid)

Fasting Required

Purpose of the Test

To help diagnose the cause of joint inflammation, pain, and/or swelling

When this test is required

Synovial fluid analysis may be requested when a doctor suspects that a patient has a condition involving one or more of their joints and some of the following signs and symptoms: Joint pain Redness over the joint Joint inflammation and swelling Synovial fluid accumulationIt is sometimes requested to monitor a patient with a known joint condition.

What the Test Detects

Synovial fluid is a thick liquid that acts as a lubricant for the major joints of the body. It is found in small quantities in the spaces between the bones in a joint, called the synovial cavity. Here the fluid is produced and contained by the synovial membranes which cover the inner surface of the cavity. Synovial fluid lubricates the joint and reduces friction during movement in the knees, shoulders, hips, hands, and feet.Synovial fluid analysis consists of inspection of fluid, as well as tests that detect changes in synovial fluid that may indicate the presence of diseases that affect joint structure and function.See MoreSee Less

Preparation for the Test

Consult with your doctor about test preparation. Synovial fluid collection and analysis may be performed after fasting or at random.

Sample Requirements

A sample of synovial fluid is collected by a doctor from the affected joint with a syringe and needle using a procedure called a joint aspiration. The sample is called a joint aspirate.

Additional Notes

Other laboratory investigations which may be requested if a doctor suspects that a patient may have a systemic infection, include a full blood count (FBC), C reactive protein (CRP), and erythrocyte sedimentation rate (ESR). If gout is suspected, the doctor will request serum uric acid or urate. Some infections such as Lyme Disease (Borreliosis) are not easily diagnosed by joint aspirate and may require a specific blood test.Joint injury, surgery, and joint replacement can increase the risk of developing an infection in a joint.

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