Laboratory: Clinical Microbiology
Test Name:
BRONCHIAL WASHINGS, CULTURE, AEROBIC BACTERIA
Test Code: BRON
Clinical Information:
Test Indications:
Bronchial washings are secretions aspirated back through a bronchoscope channel after instillation of saline into a major airway.  They do not represent material from the bronchiolar or alveolar level, in contrast to fluid obtained by bronchial alveolar lavage.  This sample type is usually contaminated with oral flora.  In intubated patients, bronchial washings are no different from an endotracheal aspirate obtained with a suction catheter.
Bronchial washings or an endotracheal aspirate are appropriate samples to obtain for investigation of the microbial etiology of hospital-acquired or ventilator-associated pneumonia.  Current North American guidelines on the management of patients with hospital-acquired and ventilator-associated pneumonia favor non-invasive respiratory sampling methods (such as bronchial washings) over invasive sampling methods including bronchial alveolar lavage.

Recommendations:
Clearly indicate on the microbiology requisition the specimen type (bronchial wash) and the test(s) requested.  In the microbiology laboratory, bronchial washings are treated like an endotracheal aspirate.  Semi-quantitative quantitative culture will be performed on bronchial washings submitted to the microbiology laboratory for bacterial culture.  Note that bronchial washings are not appropriate for recovery of anaerobes and requests for anaerobe culture will be rejected.
If Nocardia, Legionella, Mycobacteria, and/or Fungi are suspected, these should be specifically requested on the microbiology requisition.
If infection with a systemic fungus (e.g., Blastomyces dermatitidis, Coccidioides imitis, Histoplasma capsulatum, Talaromyces marneffei, Paracoccidioides brasiliensis) is suspected, notify the laboratory in advance.
The laboratory will automatically perform a Gram stain where appropriate.  This does not need to be requested on the microbiology requisition.
Please indicate what antimicrobial therapy the patient is currently receiving on the microbiology requisition (clinical details section).
For information on other microbiology tests on bronchial washings not performed by Shared Health Clinical Microbiology Laboratories (e.g., virus detection), please refer to the relevant laboratory that performs the testing.

Patient Preparation Instructions:
Follow the procedure outlined by your healthcare facility.
Accurate patient identification must be made prior to sample collection.  Patient identification should be done in accordance with site policy.
Samples and requisitions must be labeled/completed in accordance with the Shared Health Specimen Acceptance Policy.
Collection Devices:
Specimen Required: Respiratory secretions/fluid obtained by bronchial washing - A minimum of 1 mL is required. (Adult and Pediatric)
Referral:
Requisition:
Reference Values:
A descriptive report will be sent.  Semi-quantitative cultures will be performed for bacteria.  Samples that are negative for bacterial culture will be incubated for 48 hours before being reported as "No growth".
For further details on mycobacteria culture and fungal culture, refer to the LIM entries for these.
Availability:
Daily
See Also:
More Information:
Specimen Handling:
Transport to the laboratory as soon as possible.
If transport will occur within 2 hours, it is acceptable to store the specimen at room temperature (although 4°C is optimal).
If transport to the laboratory will be delayed up to 24 hours, store the specimen at 4°C.  Ensure samples that are being sent to a referral laboratory are packaged in accordance with Transport of Dangerous Goods recommendations for diagnostic samples.

References:
1.  Baselski VS, et al. Bronchoscopic diagnosis of pneumonia. Clin Micro Rev 1994;7:533-58.
2.  Kalil AC et al. Management of adults with hospital-acquired pneumonia and ventilator-associated pneumonia: 2016 clinical practice guidelines by the Infectious Diseases Society of America and the American Thoracic Society. Clin Infect Dis 2016;63:e61-111.
3.  Jorgensen JH, et al. (editors). Manual of Clinical Microbiology, 11th edition.