Laboratory Test Guide: What It Is, How the Sample Is Collected, and What Your Results Mean

This test measures specific substances in your body to help your doctor check how well certain organs are working, look for signs of illness, or monitor a condition you already have. It is a routine and safe procedure that gives your care team important information to guide decisions about your health and any treatment you may need.

The Borrelia burgdorferi IgG and IgM panel is a laboratory test that detects antibodies against the bacteria that cause Lyme disease (Borrelia burgdorferi) in the cerebrospinal fluid (CSF). CSF is the clear fluid that surrounds the brain and spinal cord. This test specifically checks for two types of antibodies: IgM (which the body produces first in response to infection) and IgG (which the body produces later as the infection progresses).

A trained healthcare professional will collect a small sample, most often a small amount of blood drawn from a vein in your arm, though sometimes a urine specimen or swab is used, depending on what your doctor has ordered. The collection usually takes only a few minutes, and you can typically return to your normal activities right afterward.

The cerebrospinal fluid sample is collected through a procedure called a lumbar puncture, also known as a spinal tap. During this procedure, a healthcare provider inserts a thin needle into the lower back to withdraw a small amount of CSF. The area is numbed first with a local anesthetic to minimize discomfort. After the sample is collected, you may be asked to lie flat for a short time to reduce the chance of a headache.

Your results show the measured values for this test, which are compared with a reference range to see whether they fall within typical limits. A value outside the range does not always mean you are sick, so your doctor will interpret it together with your symptoms, medical history, and other test results before recommending any next steps.

The test provides separate results for IgG and IgM antibodies. A positive IgM result typically indicates an early Lyme disease infection, as IgM antibodies usually appear within the first few weeks after being bitten by an infected tick. A positive IgG result usually indicates a later or longer-standing infection, as IgG antibodies develop weeks to months after the initial infection. However, results must be interpreted carefully by your healthcare provider, considering your symptoms, potential exposure to ticks, and the timing of your symptoms.