Anti-Borrelia burgdorferi IgG Immunoassay (Serum/Plasma)
This test measures antibodies in your blood that your immune system produces in response to *Borrelia burgdorferi*, the bacterium responsible for Lyme disease.
["Detects past or current Lyme disease infection by identifying your immune system’s response to the bacteria."]
Key facts at a glance
- LOINC
- 47075-7
- Short code
- COXPH1M
- Synonyms
- C burnet Ph1 IgM Titr Ser IF
- Category
- chemistry
- Sample
- serum
- Container
- Serum separator tube (SST) or red-top clot tube
- Units
- N/A
- Ref low
- 0
- Ref high
- 1
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- Indirect Immunofluorescence Assay (IFA)
- CPT
- 86638
- SNOMED
- 122606008
- Specimen volume
- 1 mL serum (minimum 0.5 mL)
- Stability
- Stable for 7 days at 2–8°C; for extended storage, freeze at -20°C or below for up to 4 weeks. Avoid repeated freeze-thaw cycles.
- Hemolysis max
- 100
- Lipemia max
- 100
- Icterus max
- 50
- TAT
- 24–72 hours
- Order
- routine
What This Test Measures
The test looks for **IgG antibodies**—a type of protein your body makes to fight infections. If you’ve been exposed to *Borrelia burgdorferi* (e.g., through a tick bite), your immune system may produce these antibodies over time. This doesn’t always mean you have active Lyme disease, but it can indicate prior exposure or a past infection.
How It Works
Your blood sample is tested using an **immunoassay** (a lab method that detects specific antibodies). If antibodies are present, the test can confirm exposure to the bacteria, though results alone don’t diagnose Lyme disease. Additional testing (like culture or PCR) may be needed for confirmation.
When You Might Need This Test
Doctors may order this test if you’ve had symptoms of Lyme disease (e.g., rash, flu-like illness, joint pain) after a tick bite, especially in areas where Lyme is common. It’s also used in follow-up for people with suspected chronic Lyme or post-treatment evaluation.
Symptoms to Watch For
Lyme disease symptoms can vary widely and may include a bull’s-eye rash (erythema migrans), fatigue, fever, muscle aches, or neurological issues (e.g., headaches, numbness). If you suspect exposure, see your doctor promptly.
Reference range
Negative: <1:16; Equivocal: 1:16–1:64; Positive: ≥1:64 (varies by laboratory). Phase 1 IgM antibodies indicate chronic Q fever infection.N/A
No fasting required. Specimen should be collected before initiation of antibiotic therapy when possible to avoid false-negative results.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical Significance
Short name
Anti-Borrelia IgG
Frequently asked questions
Why might my doctor ask for this test?
What does a positive result mean?
Can I get this test at home?
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 15, 2026. · Read our editorial policy