Bartonellaigmmsmtser
A blood test to detect IgM antibodies against Bartonella bacteria, indicating recent or current infection.
{"Detects IgM antibodies produced in early response to Bartonella infection","Helps diagnose conditions like cat-scratch disease and trench fever","Sample is collected from blood (serum)","Positive result suggests recent infection within past few weeks","Often ordered along with IgG test for complete picture"}
Key facts at a glance
- LOINC
- 109263-4
- Short code
- BARTIGM
- Synonyms
- Bartonella IgM Msmt Ser
- Category
- chemistry
- Sample
- serum
- Container
- Serum separator tube (SST), red-top tube, or tiger-top tube
- Units
- N/A
- Ref low
- 20
- Ref high
- 1
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- Immunofluorescence Assay (IFA) or Enzyme Immunoassay (EIA) for detection of IgM antibodies
- CPT
- 86611
- SNOMED
- 122548009
- Specimen volume
- 1-2 mL serum (minimum 0.5 mL)
- Stability
- Stable at room temperature for 8 hours; refrigerated (2-8°C) for 7 days; frozen (-20°C or below) for up to 30 days. Avoid repeated freeze-thaw cycles.
- Hemolysis max
- 100
- Lipemia max
- 100
- Icterus max
- 50
- TAT
- 48–168 hours
- Order
- routine
What is this test?
The Bartonella IgM Antibody test is a blood test that detects IgM antibodies against Bartonella species bacteria in your blood. IgM antibodies are the first type of antibodies your immune system produces when fighting a new infection, typically appearing within 1-2 weeks after exposure and lasting for several weeks to months.
Why might I need this test?
Your healthcare provider may order this test if you have symptoms suggesting a Bartonella infection, such as fever, swollen lymph nodes (especially after a cat scratch or bite), fatigue, or headache. Common conditions caused by Bartonella include cat-scratch disease (from cat scratches/bites), trench fever (from body lice), and Carrion's disease (from sand fly bites in South America).
How is the test performed?
A healthcare professional will draw a small blood sample from a vein in your arm. The blood is collected in a tube and sent to a laboratory for analysis. The laboratory will test your serum (the liquid part of blood after it clots) for the presence of IgM antibodies specific to Bartonella bacteria.
What do the results mean?
A positive IgM result indicates that you likely have a recent or current Bartonella infection. A negative result means no IgM antibodies were detected, but this could mean either you don't have an infection or the infection is too early (before antibodies develop) or too late (IgM has disappeared). Your provider may also order an IgG antibody test, which detects longer-lasting antibodies, to get a more complete picture of your infection status.
Are there any risks?
The risks are minimal and similar to any routine blood draw, including slight bruising, bleeding, or infection at the puncture site. Some people may feel lightheaded during or after the blood draw.
Reference range
Negative: <1:20 titer. Equivocal: 1:20-1:40. Positive: ≥1:80. Reference ranges may vary by laboratory and assay methodology.N/A
No special patient preparation required. Fasting is not necessary.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Frequently asked questions
How long does it take to get results?
Do I need to fast before this test?
What happens if my test is positive?
Can I have a Bartonella infection without symptoms?
How is Bartonella infection treated?
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