Streptococcus pyogenes (Group A Beta-Hemolytic Streptococcus) [Presence] in Throat by Culture
This laboratory test uses a throat culture to detect Streptococcus pyogenes, the bacterium that causes group A streptococcal pharyngitis. A positive result supports a diagnosis of strep throat.
["A positive throat culture confirms that group A strep bacteria are present."]
Key facts at a glance
- LOINC
- 585-0
- Short code
- Gp B Strep Throat Ql Cult
- Synonyms
- Gp B 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 Detects
The test looks for group A Streptococcus bacteria, also called Streptococcus pyogenes, in a sample taken from the throat. These bacteria commonly cause sore throat, fever, and swollen glands in the neck.
How the Test Is Performed
A healthcare professional collects material from the throat and places it on a culture plate. The laboratory monitors the sample for bacterial growth, and a positive result is reported when group A strep is identified.
Understanding the Results
A positive result means group A strep was detected. A negative result means it was not detected by the culture, although symptoms can occasionally be caused by another infection or persist despite a negative result.
Why the Test Is Ordered
A throat culture may be ordered when a clinician needs to confirm group A strep infection, particularly when rapid screening results and the patient's symptoms do not clearly establish the cause of the sore throat.
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.
◆Associated findings1
Short name
Group A Strep Throat Culture
Frequently asked questions
Does a positive result mean I have strep throat?
Why can a strep throat culture be negative?
Is a throat culture different from a rapid strep test?
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