Escherichia coli Antibody (IgG) in Serum or Plasma by Immunoassay
This test measures your immune system’s response to bacteria called *Escherichia coli* (E. coli) by detecting antibodies (IgG) your body produces to fight them. It helps identify past exposure or immune reaction to these bacteria.
["This test helps assess immune response to common gut bacteria, useful in diagnosing infections or evaluating immune function."]
Key facts at a glance
- LOINC
- 105765-2
- Short code
- E coli DNA Ct Bld Pos Qn NAA+probe
- Synonyms
- E coli DNA Ct Bld Pos Qn NAA+probe
- Category
- chemistry
- Sample
- whole-blood
- Container
- Lavender-top (EDTA)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- probe-amp-tar
- Specimen volume
- 3 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 4–24 hours
- Order
- routine
What This Test Measures
The test detects IgG antibodies specific to *E. coli*, a type of bacteria commonly found in the digestive tract. These antibodies indicate your immune system has encountered E. coli before, either through infection or vaccination (e.g., oral vaccines). The presence of these antibodies suggests your body is recognizing and responding to this bacterium.
Why It Might Be Ordered
Your healthcare provider may order this test if you have symptoms of infection (e.g., diarrhea, fever), if you’ve had recent exposure to E. coli, or if you’re being evaluated for immune-related conditions. It can also help monitor immune responses in certain medical situations.
How the Test Works
A small blood sample is taken from your arm. The serum or plasma is then tested using an immunoassay method to detect IgG antibodies against E. coli. This method uses labeled antibodies to identify and quantify your immune response.
What the Results Mean
A positive result means your body has produced IgG antibodies to E. coli, indicating prior exposure. A negative result suggests no detectable antibodies, meaning either you’ve never been exposed or your immune system hasn’t mounted a response yet. Results are qualitative (present or absent) and not tied to specific numeric ranges.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
E. coli antibodies can be useful in diagnosing or confirming past infections, especially in cases where symptoms are unclear or recurrent. They may also help evaluate immune function in patients with chronic gastrointestinal issues or immune disorders. However, this test alone cannot confirm an active infection—it only shows immune memory.
Short name
E. coli Antibody Test
Frequently asked questions
Will this test show if I currently have an E. coli infection?
How long does it take to get results?
Can I take anything before this test?
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