Streptococcus Group B Enzyme Immunoassay (Serum/Plasma)
This test measures antibodies in your blood that may help identify exposure to *Streptococcus group B* bacteria, which can cause serious infections in newborns.
["This test helps assess potential risk for neonatal infection from Group B strep bacteria."]
Key facts at a glance
- LOINC
- 49016-9
- Short code
- Streptococcus sp exoenzyme Ab Ser-aCnc
- Synonyms
- Streptococcus sp exoenzyme Ab Ser-aCnc
- Category
- coagulation
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 0.8
- Ref high
- 1.2
- Critical range
- — – 5 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 85610
- SNOMED
- 396252006
- 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
The test detects specific antibodies (immunoglobulins) produced by your immune system in response to *Streptococcus group B* bacteria. These antibodies are part of your body’s defense against infection but may indicate past or recent exposure.
Why It’s Ordered
Your healthcare provider may order this test if you have symptoms of infection, if you’re pregnant (to screen for Group B strep in newborns), or if you’re at higher risk for complications from bacterial infections.
How the Test Works
A small blood sample is taken and analyzed using an immunoassay method to detect the presence of antibodies against Group B strep. This method uses enzymes to trigger a reaction that can be measured precisely.
What the Results Mean
Positive results suggest your body has produced antibodies against Group B strep, which may indicate prior exposure or infection. Negative results mean no detectable antibodies were found in this sample.
Reference range
INR: 0.8-1.2 (warfarin: 2.0-3.0)N/A
Inform your healthcare provider if you are taking blood thinners. No special preparation required.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical Significance
Short name
Group B Streptococcus Antibody Test
Frequently asked questions
This test is primarily used in prenatal care to identify women colonized with Group B strep, allowing for preventive measures like antibiotic treatment during labor to reduce the risk of neonatal infection.
What does a positive result mean for me?
How soon will I get my 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