Antibody to Streptococcus pneumoniae (Serum) – Qualitative
This test checks for antibodies in your blood that may indicate a past or current infection with *Streptococcus pneumoniae*, a common bacterial cause of pneumonia, ear infections, and other respiratory illnesses.
["A positive result may suggest recent exposure or infection by this bacterium."]
Key facts at a glance
- LOINC
- 13166-4
- Short code
- Deprecated S pneum23 Ab Ser-aCnc
- Synonyms
- Deprecated S pneum23 Ab Ser-aCnc
- 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 qualitative test detects the presence of antibodies against *Streptococcus pneumoniae* in your serum. Antibodies are proteins your immune system produces in response to infection. If your body has encountered this bacteria before or is fighting an active infection, these antibodies will be present.
Why It’s Done
Doctors may order this test if you have symptoms of pneumonia, sinusitis, or other respiratory infections, especially if you’re at higher risk (e.g., young children, elderly adults, or those with weakened immune systems). It can also help confirm a diagnosis in certain clinical settings.
How the Test Works
A blood sample is taken, and the serum is analyzed to detect specific antibodies against *Streptococcus pneumoniae*. The result is reported as positive or negative, indicating whether antibodies were found.
What the Results Mean
A **positive** result suggests your immune system has recognized *Streptococcus pneumoniae* (either from past infection or vaccination). A **negative** result means no detectable antibodies were found at the time of testing.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
S. pneumoniae Antibody Screen
Frequently asked questions
Why might this test be important?
What does a positive result mean for my health?
Could this test affect my vaccination schedule?
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.
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Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy