Description
This test is used to detect antibodies against Borrelia burgdorferi, the bacteria that causes Lyme disease. It helps diagnose both current and past infections.
How the Test Works
- Total Antibody Screen: The initial test measures overall antibodies (IgG and IgM) to Borrelia in the blood.
- Reflex to Immunoblot: If the total antibody screen is positive or equivocal, the sample is automatically tested using immunoblot (Western blot) to identify specific IgG and IgM antibodies. This two-step approach increases the accuracy of Lyme disease diagnosis.
Purpose of the Test
- Diagnose Lyme disease: Particularly in patients with symptoms such as fever, fatigue, joint pain, or the characteristic bullseye rash.
- Assess disease stage: IgM antibodies typically appear in early infection, while IgG antibodies indicate later-stage or past infection.
- Guide treatment decisions: Positive results can help clinicians determine the need for antibiotic therapy or further evaluation.
When to Test
- Recent tick bite with symptoms of Lyme disease
- Unexplained joint, neurological, or cardiac symptoms in areas where Lyme disease is common
- Follow-up for previously treated Lyme disease, if new symptoms occur
Fasting
- Fasting is not required.
This test is considered the standard approach for laboratory confirmation of Lyme disease, combining sensitivity from the initial antibody screen with specificity from the immunoblot reflex.
