Anaerobic and Aerobic Culture and Gram Stain
Also known as: Anaerobic Culture, Abscess, Anaerobic Culture, Body Fluid, Anaerobic Culture, Wound, Culture, Anaerobic, Wound Anaerobic Culture
Use
Isolate and identify anaerobic pathogenic organisms; determine susceptibility of isolates (extra charge). When actinomycetes are suspected a specific request must be made. Anaerobic cultures are indicated particularly when suspected infections are related to gastrointestinal tract, pelvic organs, associated with malignancy, related to use of aminoglycosides; or occur in a setting in which the diagnosis of gas gangrene or actinomycosis is considered. Anaerobic culture is especially indicated when an exudate has a foul odor or if the exudate has a grayish discoloration and is hemorrhagic. Frequently, more than one organism is recovered from an anaerobic infection.
Special Instructions
The test request form must specify the site of the specimen, patient age, current antibiotic therapy, clinical diagnosis, and time of collection. Collection is crucial to avoid contamination from indigenous flora. Aspirations are preferred over swabs. For extended incubation, refer to test codes 180803 or 008900. Inappropriate specimens for anaerobic cultures include throat, sputum, voided urine, and superficial wounds due to contamination risk. Swabs/specimen must be placed in anaerobic transport media immediately to ensure organism viability.
Limitations
Anaerobic cultures are applicable primarily for blood, pleural fluid, and specific aspirates due to established validity. Blood cultures are only positive in less than 5% of anaerobic pulmonary infections. Specimens in anaerobic transport are suboptimal for aerobic fungus cultures. Extended incubation or specific media are needed for Mycobacterium or Nocardia. Specimens from endogenous anaerobic flora sites (e.g., throat, genital swabs) are unsuitable for anaerobic culture. Bronchoscopically obtained specimens can be misleading due to contamination with organisms from the oropharynx.
Methodology
Culture-based
Biomarkers
LOINC Codes
- 635-3
- 634-6
- 664-3
Result Turnaround Time
4-7 days
Related Documents
For more information, please review the documents below
Specimen
Other
Volume
Not provided
Minimum Volume
0.5 mL
Container
Aerobic/anaerobic bacterial swab transport containing gel medium or anaerobic transporter and one prepared smear in slide carrier; ESwab™ transport
Collection Instructions
Pus or fluid should be obtained via needle aspiration from sterilized skin/mucosal surfaces. Use a sterile plastic catheter for aspirating open lesions. Swab specimens using anaerobic transport media immediately.
Patient Preparation
Sterile preparation of the aspiration site is imperative.
Storage Instructions
Specimens should be maintained at room temperature. ESwab™ transport not recommended for more than 48 hours due to viability loss.
Causes for Rejection
Specimens from sites that have anaerobic bacteria as indigenous flora will not be cultured anaerobically. Unlabeled or name-discrepant specimens, inappropriate transport tubes, oxygen-exposed swabs, prolonged transport delay.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 24 to 72 hours |