Definition of Culture - joint fluid:

Joint fluid culture is a laboratory test to detect infection-causing organisms in a sample of fluid surrounding a joint.

How the test is performed:

A sample of joint fluid is needed. This may be done in a doctor's office using a needle, or during an operating room procedure. For more information on this procedure, see joint fluid aspiration.

The fluid sample is sent to a laboratory where it is placed in a special dish and watched to see if bacteria, fungi, or viruses grow. This is called a culture.

If such microorganisms are detected, other tests may be done to further identify the infection-causing substance and determine the best treatment.

How to prepare for the test:

There is no special preparation needed for the lab culture. For information on preparing for the removal of joint fluid, see joint fluid aspiration.

How the test will feel:

The joint fluid culture is done in a laboratory and does not involve the patient.

For information on how the procedure to remove joint fluid feels, see joint fluid aspiration.

Why the test is performed:

Your doctor may order this test if you have unexplained pain and inflammation of a joint or a suspected joint infection.