Legionella Pneumophila Detection in Sputum (Qualitative)
This test checks for the presence of *Legionella pneumophila*, a bacterium linked to Legionnaires’ disease, in your sputum sample. It helps doctors diagnose infections caused by this germ.
["A positive result may indicate Legionnaires’ disease and guide treatment decisions."]
Key facts at a glance
- LOINC
- 592-6
- Short code
- Deprecated Legionella Sputum trach asp C
- Synonyms
- Deprecated Legionella Sputum trach asp C
- Category
- chemistry
- Sample
- sputum
- Container
- Sterile sputum container
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- organism-specific-culture
- Specimen volume
- 3-5 mL
- Stability
- Room temperature: 2h, Refrigerated: 24h
- TAT
- 4–24 hours
- Order
- routine
Why This Test Is Done
Your doctor may order this test if you have symptoms like fever, cough, shortness of breath, or chest pain—especially if you’ve recently traveled, lived in a large building, or been exposed to contaminated water. It’s also used in outbreaks or when other tests are inconclusive.
How the Test Works
The test detects genetic material (DNA) from *Legionella pneumophila* in your sputum using a molecular method. Results are typically available within 24–48 hours, though some labs may use culture methods (which take longer).
What to Expect Before the Test
You’ll likely need to provide a sputum sample (saliva from your throat/lungs) by coughing into a sterile container. If you’re unable to produce sputum, your doctor may use a nasal swab or other methods. Follow any instructions to prepare (e.g., avoiding cough suppressants).
What to Expect During the Test
The lab processes your sample to identify the bacterium. No special preparation is needed beyond providing the sample correctly. Results are reviewed by a medical professional to confirm diagnosis.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
A positive result strongly suggests *Legionella pneumophila* infection, which requires prompt antibiotic treatment (e.g., azithromycin or doxycycline). A negative result doesn’t always rule out infection—other causes of pneumonia (e.g., viruses, fungi) may be present. Your doctor will adjust care based on symptoms, exposure history, and test results.
Short name
Legionella Sputum Test
Frequently asked questions
What Does a Positive Result Mean?
What If I Get a Negative Result?
How Long Until I Know 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