IgM and IgG Antibody Blood Test
This test detects IgG and IgM antibodies against Borrelia burgdorferi, the bacterium that causes Lyme disease, using immunoblot technique.
{"Confirms Lyme disease infection detected by initial screening","IgM antibodies typically appear first (early infection)","IgG antibodies develop later (weeks to months after tick bite)","Results should be interpreted with clinical symptoms","Timing of testing is important for accuracy"}
Key facts at a glance
- LOINC
- 98204-1
- Short code
- BORWB
- Synonyms
- B burgdor IgG+IgM bands Pnl Ser IB
- Category
- chemistry
- Sample
- serum
- Container
- Serum separator tube (SST), red-top tube, or tiger-top tube
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 0–120 years
- Method
- Immunoblot (Western Blot) for detection of IgG and IgM antibodies against Borrelia burgdorferi specific protein bands
- CPT
- 86617 x2
- SNOMED
- 122640000
- Specimen volume
- 1-2 mL of serum (minimum 0.5 mL)
- Stability
- Serum stable at room temperature for 8 hours, refrigerated (2-8°C) for 7 days, frozen at -20°C or below for up to 4 weeks. Avoid repeated freeze-thaw cycles.
- Hemolysis max
- 2
- Lipemia max
- 2
- Icterus max
- 2
- TAT
- 24–72 hours
- Order
- routine
This blood test measures two types of antibodies, IgM and IgG, which are proteins your immune system produces to fight infections. By looking at both, your doctor can get a clearer picture of whether your body is dealing with a current infection or responding to one you had in the past.
The Borrelia burgdorferi IgG and IgM bands panel is a confirmatory blood test that detects antibodies specific to the bacterium causing Lyme disease. The test uses immunoblot (Western blot) technique to identify multiple protein bands, providing more detailed information than initial screening tests.
Your doctor may order this test to help determine whether you have been exposed to a recent or previous infection, to clarify a diagnosis when your symptoms are not specific, or to evaluate how your immune system is responding after an illness or vaccination.
This test is primarily used to confirm positive or borderline results from initial Lyme disease screening tests like ELISA. It helps distinguish between true infections and false positives, and can indicate whether the infection is recent (IgM) or potentially older (IgG).
IgM antibodies are usually the first ones your body makes, appearing within days of an infection and often suggesting a current or very recent illness. IgG antibodies take longer to develop but tend to stay in your blood for months or years, which can indicate past exposure or lasting protection.
IgM antibodies are the first antibodies your body produces in response to infection. They typically appear within 1-2 weeks after infection and indicate early or recent exposure to Borrelia burgdorferi. IgG antibodies develop later, usually within 4-6 weeks, and can persist for months or years. The presence of IgG antibodies may suggest a longer-standing infection or previous exposure.
A healthcare professional will clean the skin on your arm, wrap a band around your upper arm, and draw a small blood sample from a vein, usually on the inside of your elbow or the back of your hand. The sample is then sent to a laboratory, and your results are typically ready within a few days.
A blood sample is drawn from a vein in your arm. The sample is then sent to a laboratory where it undergoes immunoblot analysis to detect specific antibodies against Borrelia burgdorferi proteins.
Reference range
Negative. Positive when 5 or more IgG bands (of 10 evaluated: 18, 21, 28, 30, 39, 41, 45, 58, 66, 93 kDa) are reactive, or when 2 or more IgM bands (of 3 evaluated: 23, 39, 41 kDa) are reactive, per CDC/AAP criteria for Lyme disease serologic interpretation.N/A
No fasting required. Specimen collection should ideally be performed at least 2-4 weeks after suspected tick exposure or onset of symptoms to allow for detectable antibody response. Inform clinician of recent antibiotic use, current illness, and vaccination history.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Positive IgM with negative IgG suggests early Lyme disease infection, typically within the first few weeks of the tick bite. Positive IgG indicates either current or past infection. Negative results may mean no infection, or testing done too early before antibodies developed. Results must always be interpreted alongside clinical symptoms like the characteristic erythema migrans (bull's-eye rash), joint pain, or neurological symptoms.
Frequently asked questions
How long after a tick bite should I wait to get tested?
Do I need to fast before this test?
What do the bands on the immunoblot mean?
Can this test tell if I have an active infection?
If I had Lyme disease before, will this test still be positive?
Sources
- 1
- 2
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 15, 2026. · Read our editorial policy