Borrelia burgdorferi IgG Antibody (Serum) by Immunofluorescence Assay
This test detects antibodies to *Borrelia burgdorferi*, the bacterium responsible for Lyme disease. It helps diagnose infection after exposure.
["This blood test checks for Lyme disease antibodies, often used after tick bites or symptoms like rash or joint pain."]
Key facts at a glance
- LOINC
- 31312-2
- Short code
- COXPH1IGA
- Synonyms
- C burnet Ph1 IgA Ser-aCnc
- Category
- chemistry
- Sample
- serum
- Container
- Serum separator tube (SST) or red-top tube; serum aliquot in plastic vial
- Units
- N/A
- Ref low
- 0
- Ref high
- 1
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- Enzyme-linked immunosorbent assay (ELISA) or Indirect immunofluorescence assay (IFA)
- CPT
- 86638
- SNOMED
- 12210001
- Specimen volume
- 0.5 to 1 mL serum
- Stability
- Room temperature: 8 hours; Refrigerated (2-8°C): 7 days; Frozen (-20°C or below): 30 days. Avoid repeated freeze-thaw cycles.
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 24–72 hours
- Order
- routine
What This Test Measures
The test identifies antibodies produced by your immune system in response to *Borrelia burgdorferi*. If present, they suggest past or current infection. Antibodies may take weeks to develop after exposure, so results may not be immediate.
Why It’s Ordered
Your healthcare provider may order this test if you have symptoms like fever, fatigue, or a bullseye rash (erythema migrans) after a tick bite, or if you live in an area with Lyme disease risk. It’s also used to monitor treatment progress.
Sample Collection
A blood sample is drawn from a vein, usually in your arm. You may feel a small pinch, but it’s quick. No special preparation is needed, though fasting isn’t required.
Possible Results
A positive result means your body has detected antibodies to *Borrelia burgdorferi*, indicating exposure. A negative result suggests no detectable antibodies at this time. Results alone don’t confirm Lyme disease; symptoms and medical history are also considered.
Reference range
Negative: <1:16; Equivocal: 1:16 to 1:32; Positive: ≥1:64 (titers vary by laboratory method). Refer to laboratory-specific reference ranges.N/A
No fasting required. Patients should inform their healthcare provider of any recent antibiotic use or ongoing immunosuppressive therapy, as these may affect antibody response.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
Borrelia IgG Antibody (Serum)
Frequently asked questions
What does a positive result mean?
What does a negative result mean?
How soon will I get results?
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