Streptococcus throat culture with qualitative detection of group A Streptococcus (GAS) antibodies (e.g., anti-streptolysin O, ASO)
This test involves collecting a sample from your throat to check for bacteria that may cause strep throat. It also measures certain antibodies your body produces in response to these bacteria.
["Helps diagnose strep throat and assess immune response to bacterial infection."]
Key facts at a glance
- LOINC
- 546-2
- Short code
- B-Hem Strep Throat Ql Cult
- Synonyms
- B-Hem Strep Throat Ql Cult
- 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
- Method
- organism-specific-culture
- 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 includes two parts: a throat culture to identify live bacteria (such as Group A Streptococcus) and antibody testing to detect immune system responses. The culture helps determine if bacteria are present, while the antibody test looks for signs of past or ongoing infection.
How the Test Works
A swab is taken from your throat to grow bacteria in a lab. Separately, blood or serum is tested for specific antibodies (like anti-streptolysin O) that your immune system makes when fighting Group A Streptococcus. These antibodies can indicate a history of infection.
Why It’s Done
Doctors may order this test if you have symptoms like sore throat, fever, or swollen lymph nodes, especially if strep throat is suspected. Antibody testing can help confirm past infection or monitor immune response.
What to Expect
You’ll have a quick throat swab, and blood may be drawn separately. Results from the culture take 24–48 hours, while antibody results may be available sooner. Follow-up may include antibiotics if bacteria are confirmed.
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.
Positive culture results may guide treatment with antibiotics to stop bacterial spread. Antibody levels can help diagnose past infections, monitor immune function, or assess exposure risk. High antibody titers may indicate ongoing immune activity or recent infection.
Short name
Throat Culture for Group A Strep Antibody Screen
Frequently asked questions
How long does it take to get results?
Can I take antibiotics before getting tested?
Does this test detect all types of strep throat?
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