Gram-Stain Qualitative Analysis of Nasopharyngeal Swab (Bacterial Culture)
This test examines a sample taken from your nose to identify bacteria using a simple staining method. It helps determine if bacteria are present and, by visual inspection, their general shape and grouping.
["Assists in diagnosing infections like colds, ear infections, or respiratory illnesses caused by bacteria."]
Key facts at a glance
- LOINC
- 76582-6
- Short code
- S agalact cfb Swab Ql NAA+probe
- Synonyms
- S agalact cfb Swab Ql NAA+probe
- Category
- coagulation
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- probe-amp-tar
- 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
How the Test Works
A swab is gently inserted into your nasal passage to collect bacteria. The sample is then stained with a dye (Gram stain) to highlight bacterial cells. Microscopic examination reveals the presence and type of bacteria, though it does not confirm specific bacterial species without further testing.
When You Might Need This Test
Your healthcare provider may recommend this test if you have symptoms like persistent sore throat, nasal congestion, or ear pain that suggest a bacterial infection, especially if antibiotics are being considered.
What to Expect Before the Test
No special preparation is needed. You may experience mild discomfort or slight irritation during the swab insertion, but it usually takes less than a minute. Avoid using nasal decongestants or sprays 24 hours before the test if possible.
What to Expect During the Test
The swab is inserted gently into your nostril, and you may be asked to breathe through your mouth to keep your nasal passages open. The procedure is quick and painless, though some patients may feel slight pressure or a tickle.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
This test provides preliminary information about bacterial presence but is not definitive for identifying specific bacteria. It is often used as an initial screening tool to guide further diagnostic steps, such as bacterial culture or antibiotic sensitivity testing, if needed. Results help determine whether antibiotics are appropriate for your symptoms.
Short name
Gram Stain Swab Test
Frequently asked questions
How long does it take to get results from this test?
What does a positive result mean?
Can I take antibiotics before knowing the results?
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