Understanding Your Laboratory Test: What It Is, How It Is Performed, and What Your Results Mean for Your Health

This test is a laboratory analysis that measures specific substances in a sample of your blood, urine, or other body tissue to help your doctor evaluate how well your body is functioning and to detect signs of disease, infection, or other health problems.

This test looks for IgG antibodies specifically targeting the 93kD protein of Borrelia burgdorferi, the bacterium that causes Lyme disease. The test is performed on synovial (joint) fluid collected from the affected joint through a procedure called arthrocentesis (joint fluid aspiration).

The test is usually performed by a trained healthcare professional who collects a small sample, most often blood drawn from a vein in your arm, and sends it to a certified laboratory where specialized equipment analyzes it and reports the findings to your doctor.

A healthcare provider will insert a needle into the affected joint to withdraw synovial fluid. This fluid is then sent to a laboratory where it is tested using immunoblot (Western blot) technique to detect the presence of IgG antibodies specific to the 93kD protein of Borrelia burgdorferi.

Your doctor may order this test to help diagnose a medical condition, monitor an illness you already have, check how well a current treatment is working, or screen for potential problems as part of a routine health examination before symptoms appear.

This test is typically ordered when a patient has symptoms of joint inflammation (such as swelling, pain, or limited movement) and has a known or suspected history of Lyme disease exposure. It helps determine if the joint symptoms are due to Lyme arthritis.

Your results will be compared with established reference ranges, and values outside the normal range may suggest an underlying condition; however, only your healthcare provider can interpret your results accurately in the context of your symptoms, medical history, and overall health.

A positive result indicates the presence of IgG antibodies against the 93kD protein of Borrelia burgdorferi in the joint fluid, suggesting that the bacterium is present in the joint and may be causing the inflammatory symptoms. A negative result suggests no detectable antibodies in the joint fluid, though this does not completely rule out Lyme disease as the cause of symptoms.