Borrelia burgdorferi IgG Antibody by Immunofluorescence (Serum/Plasma)

What This Test Measures

The test looks for specific antibodies (IgG) produced by your immune system in response to *Borrelia burgdorferi*. These antibodies are created when your body fights the bacterium, which can cause Lyme disease. The immunofluorescence method detects these antibodies by binding them to a fluorescent marker, making them visible under a microscope. This helps confirm whether you’ve been exposed to the bacteria or if an infection is active.

Why It’s Done

Your healthcare provider may order this test if you have symptoms like fever, fatigue, joint pain, or a bullseye rash (erythema migrans), which are common in Lyme disease. It’s also used to monitor treatment progress or check for early infection when other tests are inconclusive.

How It’s Performed

A blood sample is taken from a vein in your arm. The serum or plasma is then tested in a lab using immunofluorescence to identify the presence of *Borrelia burgdorferi* antibodies. Results are qualitative (positive or negative) rather than quantitative.

What the Results Mean

A **positive** result indicates the presence of antibodies, suggesting past or current exposure to *Borrelia burgdorferi*. A **negative** result means no detectable antibodies were found in this sample. Results alone don’t confirm Lyme disease—symptoms and clinical evaluation are also needed.