Streptococcus pneumoniae Antibody (IgG) by Immunoassay, Serum/Plasma
This test measures your immune system’s response to *Streptococcus pneumoniae* (pneumococcus), a common bacteria that can cause pneumonia, ear infections, or meningitis. It helps assess past exposure or immunity to the germ.
["This test helps doctors check if your body has developed antibodies against *Strep pneumoniae* after infection or vaccination."]
Key facts at a glance
- LOINC
- 88275-3
- Short code
- S pneumoniae gryB Bld Pos Ql Probe
- Synonyms
- S pneumoniae gryB Bld Pos Ql Probe
- Category
- coagulation
- Sample
- whole-blood
- Container
- Lavender-top (EDTA)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- probe
- 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
Why Is This Test Done?
Your doctor may order this test if you have symptoms of pneumonia, recurrent infections, or if you’re at higher risk (e.g., elderly, immunocompromised, or with chronic lung disease). It can also help evaluate immunity after vaccination or monitor long-term exposure.
What Does a Positive Result Mean?
A positive result indicates your body has produced antibodies against *Strep pneumoniae*, suggesting past infection or vaccination. This doesn’t confirm current illness but may help guide treatment or prevention strategies.
Sample Collection and Preparation
A blood sample is drawn from a vein, usually in your arm. The blood is processed into serum or plasma for testing. No special preparation is needed, but fasting may be advised depending on your doctor’s instructions.
What to Expect After Testing
You’ll likely feel minor discomfort from the needle, but most people recover quickly. Results are usually ready within 1–3 business days. Follow up with your doctor if you have questions about your results.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
IgG Antibody to *Strep Pneumoniae*
Frequently asked questions
This test supports diagnosis of past *Strep pneumoniae* infection or evaluates immunity status, especially in patients with recurrent infections or those who’ve received pneumococcal vaccines. It’s not used to diagnose active illness but can inform long-term prevention plans.
Antibodies typically appear within 1–2 weeks after infection or vaccination. However, levels may vary, so results should be interpreted alongside clinical symptoms and medical history.
This test detects antibodies against the most common *Strep pneumoniae* strains, but some less common strains may not be covered. Your doctor will consider the specific strain relevant to your symptoms.
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