IgM Antibody to *Borrelia burgdorferi* (Lyme Disease)
This test measures the presence of IgM antibodies against the bacteria that cause Lyme disease, which is spread through tick bites. It helps determine if you may have recently been infected.
["IgM antibodies can indicate a recent Lyme disease infection by detecting the body’s immune response to the bacteria."]
Key facts at a glance
- LOINC
- 110178-1
- Short code
- L braziliensis IgM Msmt Ser
- Synonyms
- L braziliensis IgM Msmt Ser
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 82784
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
What This Test Measures
IgM antibodies are a type of immune protein produced by your body in response to infection. In Lyme disease, these antibodies form shortly after infection but typically decline over weeks to months. This test specifically looks for IgM antibodies against *Borrelia burgdorferi*, the bacterium responsible for Lyme disease.
Why It Might Be Ordered
Your healthcare provider may order this test if you have symptoms such as a bullseye rash (erythema migrans), flu-like illness, joint pain, or neurological issues (like headaches or numbness) that could be linked to Lyme disease. It’s also used in follow-up testing after a suspected exposure or if symptoms persist.
What to Expect Before the Test
No special preparation is needed. You’ll provide a blood sample, usually drawn from your arm. The test is quick and typically done in a lab setting. If you’re pregnant, have a bleeding disorder, or take blood-thinning medications, let your provider know before the test.
What to Expect After the Test
After the blood is drawn, you may feel slight discomfort or bruising at the site. You can resume normal activities immediately. Results may take a few days to a week, depending on the lab. Your provider will discuss the findings with you.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Positive IgM results suggest recent infection with *Borrelia burgdorferi* and may indicate an active Lyme disease infection. However, IgM levels can drop quickly, so a positive result doesn’t always mean you’re currently infected. False positives can occur, especially if you’ve been previously exposed or have other autoimmune conditions. Your provider may order additional tests (like IgG or PCR) to confirm diagnosis and guide treatment.
Short name
IgM Lyme Antibody
Frequently asked questions
How long does it take to get results?
Can I have false-positive results?
What if my test is positive but I don’t have symptoms?
Sources
- 1
- 2Lab Tests OnlineSource
- 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 16, 2026. · Read our editorial policy