Serum or plasma concentration of immunoglobulin G (IgG) antibodies against pneumococcal polysaccharides (qualitative or semi-quantitative screening)
This test measures whether your body has produced antibodies to certain bacteria called pneumococci, which can cause serious infections like pneumonia, bloodstream infections, or meningitis.
["Helps identify if your immune system has recognized pneumococcal bacteria, useful in assessing risk for infections or evaluating immune response after vaccination."]
Key facts at a glance
- LOINC
- 85973-6
- Short code
- S pneum Da 12F Ab Ser Ql
- Synonyms
- S pneum Da 12F Ab Ser Ql
- Category
- coagulation
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- 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
This test detects the presence of specific antibodies (IgG) your immune system produces in response to exposure to pneumococcal bacteria. These antibodies are part of your body’s defense mechanism against these bacteria, which can cause infections in the lungs, sinuses, or bloodstream.
Why It Might Be Ordered
Your healthcare provider may order this test if you have a history of pneumococcal infections, are at high risk (e.g., due to weakened immune systems, chronic illnesses, or age), or if you’re considering vaccination to prevent pneumococcal disease.
What to Expect Before the Test
No special preparation is needed. You may have a simple blood draw, where a small amount of blood is taken from a vein in your arm. If you’re taking blood from a different site (like a fingerstick), a small amount of urine or saliva might be used instead.
What to Expect During the Test
The test involves drawing a small sample of blood, urine, or saliva to check for antibodies. Results are typically available within a few days, depending on lab processing.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Positive results indicate your immune system has detected and produced antibodies against pneumococcal bacteria, which may suggest past exposure or vaccination. Negative results mean no detectable antibodies, which could mean you haven’t been exposed or vaccinated yet. This can guide decisions about vaccination or further monitoring.
Short name
Pneumococcal Antibody Screening (IgG)
Frequently asked questions
What does a positive result mean?
What if my test is negative?
Does this test replace a vaccine?
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