Understanding Your Laboratory Test: A Patient's Guide to Testing, Sample Collection, and What the Results Mean
A laboratory test that identifies and grows bacteria from fluid samples to diagnose infections.
{"This test detects harmful bacteria in body fluids like fluid around lungs, joints, or abdomen","A sample is collected and sent to a lab where bacteria are grown and identified","Results help doctors choose the right antibiotic treatment","Results typically take 2-5 days as bacteria need time to grow","Your doctor will discuss results and next steps with you"}
Key facts at a glance
- LOINC
- 610-6
- Short code
- BFID
- Synonyms
- Bacteria Fld Aerobe Cult
- Category
- chemistry
- Sample
- serum
- Container
- Sterile, leak-proof container; blood culture bottles for some fluid types; sterile screw-cap tube or vacuum transport system
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- ≥ 0 years
- Method
- aerobic-culture
- CPT
- 87070
- SNOMED
- 441903009
- Specimen volume
- Variable by source: 1-5 mL minimum for most body fluids; larger volumes (5-10 mL) preferred for synovial and peritoneal fluids to maximize recovery
- Stability
- Room temperature: deliver to laboratory within 2 hours. If delayed, refrigerate at 2-8°C for up to 24 hours (except for CSF and blood culture bottles which should not be refrigerated)
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 48–168 hours
- Order
- routine
What is this test and why has my doctor ordered it for me?
Aerobic bacterial culture is a laboratory test that detects and identifies bacteria in body fluids. Body fluids that may be tested include pleural fluid (around the lungs), peritoneal fluid (in the abdomen), synovial fluid (in joints), cerebrospinal fluid, or wound drainage. The test uses aerobic culture methods, meaning it grows bacteria that need oxygen to survive.
How is the sample collected, and what can I expect during the collection process?
A healthcare provider will collect the fluid sample using a needle and syringe. The procedure depends on where the fluid is located in your body. For example, thoracentesis collects fluid from around the lungs, while paracentesis collects fluid from the abdomen. The area will be cleaned and numbed to minimize discomfort. The sample is then placed in a sterile container and sent to the laboratory for analysis.
What happens in the laboratory after my sample is sent for testing?
In the lab, the fluid sample is placed on special growth materials and kept at body temperature. If bacteria are present, they will multiply over several days. Laboratory technicians then identify the specific type of bacteria and perform antibiotic sensitivity testing (susceptibility testing) to determine which antibiotics can effectively treat the infection.
How should I prepare for this test, including fasting or medication instructions?
No special preparation is usually needed for this test. Your healthcare provider will give you specific instructions if needed. Tell your doctor about any medications you are taking, as some antibiotics may affect test results. Follow all instructions about fasting or medication adjustments before the procedure.
Are there any risks or side effects from this test that I should know about?
The main risks are related to the fluid collection procedure and may include bleeding, infection, or discomfort at the puncture site. These risks are generally minor and uncommon. Your healthcare provider will monitor you for any complications after the sample is collected.
Reference range
No growth of pathogenic bacteria. Results reported as organism identified (genus and species) with antimicrobial susceptibility results when clinically indicated.N/A
No special patient preparation required. Specimen should be collected prior to initiation of antimicrobial therapy whenever possible. Strict aseptic technique is essential. Disinfect skin or puncture site with appropriate antiseptic and allow to dry before collection.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
This test is crucial for diagnosing bacterial infections in body cavities and spaces. Positive results confirm a bacterial infection and identify the specific organism causing it. This information is essential for selecting appropriate antibiotic treatment. The antibiotic sensitivity testing helps ensure the chosen treatment will be effective against the specific bacteria. This test is commonly used for patients with fever, pain, or swelling in the chest, abdomen, or joints where infection is suspected.
Frequently asked questions
How long does it take to get results?
What does a negative result mean?
What happens if bacteria are found?
Do I need to do anything after the test?
Sources
- 1
- 2
- 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