Mycoplasma pneumoniae respiratory culture (lower respiratory tract)
This test checks for the presence of *Mycoplasma pneumoniae*, a bacteria that can cause respiratory infections like pneumonia or bronchitis, particularly in the lower airways.
["A culture helps confirm if this bacteria is causing your symptoms and guides treatment decisions."]
Key facts at a glance
- LOINC
- 91776-5
- Short code
- Resp Mycoplasma Lower resp Cult
- Synonyms
- Resp Mycoplasma Lower resp Cult
- Category
- chemistry
- Sample
- plasma
- Container
- Lavender-top (EDTA) or Green-top (Heparin)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- organism-specific-culture
- 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
Why This Test Is Done
Your healthcare provider may order this test if you have symptoms like persistent cough, fever, or difficulty breathing that suggest a lower respiratory infection. It’s especially useful when other tests (like rapid antigen tests) are inconclusive or when the infection is suspected to be caused by *Mycoplasma pneumoniae*.
What to Expect Before the Test
You’ll likely provide a sample from your lower respiratory tract, such as sputum or induced sputum (a sample collected by breathing in a saline solution to loosen mucus). If done in a lab, you may receive instructions to collect the sample at home or have it collected during a doctor’s visit.
What Happens During the Test
The sample is sent to a lab where it’s cultured in a controlled environment to grow any bacteria present. Results may take several days to weeks, as bacterial growth can be slow for *Mycoplasma pneumoniae*.
What the Results Mean
A positive result means *Mycoplasma pneumoniae* was detected in your sample. This confirms the infection and helps your provider choose the best treatment, such as antibiotics. A negative result means the bacteria wasn’t found, but other causes of your symptoms could still be present.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical Significance
Frequently asked questions
Mycoplasma pneumoniae is a common cause of atypical pneumonia, often misdiagnosed as viral or other bacterial infections. Early identification is important because it can lead to targeted antibiotic therapy, reducing complications like ear infections, sinusitis, or chronic lung issues in some cases.
Results typically take 5 to 14 days or longer, depending on the lab’s processing time. Some labs may offer preliminary guidance if they detect the bacteria early, but final confirmation usually requires waiting for full culture growth.
If your symptoms improve, it doesn’t necessarily mean the test is negative. Some infections resolve on their own, and antibiotics may not be needed if the cause isn’t confirmed. However, if your symptoms worsen or persist, follow up with your provider to discuss further testing or treatment.
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