Advanced Diagnostic Laboratories

Respiratory Culture

Test Code

CXRES

Description

Respiratory culture is a bacterial culture used to determine the causative agent for pneumonia and other lower respiratory tract infections. This test includes a Gram stain and culture. For cystic fibrosis patients, please refer to the Cystic Fibrosis culture.

Collect

Sputum: Collect in a sterile container from a deep cough while trying not to expectorate saliva or postnasal discharge. First morning expectorant is highest quality of sample.
Induced sputum: Patient inhales sterile saline and expels into a sterile container.
Bronchial wash: Inject sterile saline into the major bronchi using a bronchoscope, then suction the saline into a sterile container.
Bronchoalveolar lavage (BAL): Collected from the distal bronchioles and alveoli in the same manner as the bronchial washing.
Protected brush: Double catheter brush is used to collect material from the airway wall via a bronchoscope. Protected bronchial brush is the only source that includes anaerobic testing.
Fine Needle Aspirate: Material from peripheral lung lesion or abscess cavity is aspirated.
All specimen sources need to be collected in a sterile container or a syringe. Remove the needle and cap syringe before sending to laboratory.

Preferred volume: 3 mL
Minimum Volume: 1 mL

Patient Prep

Avoid antibiotic administration prior to sample collection. For sputum, have patient brush teeth with no toothpaste, swish water, and spit to reduce normal oral flora from contaminating sputum.

Unacceptable Conditions

Gram stain smears containing >25 squamous epithelial cells per low powered filed. This is indicative of contamination with oral flora.
Specimens received outside of temperature storage requirements
Specimens received outside of stability time frame
Specimens that do not meet the minimum volume requirement
Specimens in non-sterile containers
Specimens from a source not acceptable for this testing
Specimens that are excessively leaking
Mislabeled or unlabeled specimen

Stability

For optimal recovery of potential pathogens, specimens should arrive within 2 hours at room temperature (20-25°C)
If transportation is delayed, specimens must be refrigerated (2-8°C) for a maximum of 24 hours
Sputum mailers will be accepted up to 5 days at room temperature (20-25°C) and reported with a suboptimal disclaimer

Notes

If a specimen is received between 24 hours and 5 days from collection AND has been stored at 2-8°C, the specimen will be processed with a suboptimal disclaimer.

Performed

7 days a week from 8am to 6pm

Methodology

Aerobic bacterial culture (anaerobic culture added to protected bronchial brush)

Turnaround Time

3-5 days

Department

Microbiology Lab

Synonyms

Lower respiratory culture

Study Offerings

CAP/CLIA

Reference Interval

No respiratory pathogens isolated
Semi-quantification of normal respiratory flora

Interpretation

The table below describes reportable organisms and if antimicrobial suscecdptibility testing (AST) is routinely included. If susceptibilities are needed for an organism that AST is not routinely included, please submit the request through EPIC using the OP Add-On/Comm Message type addressed to NJH LAB ADD-ON POOL.

Threshold for reporting	Organism	Testing performed
Any	Achromobacter spp.	ID and AST
	Acinetobacter spp.	ID and AST
	Bacillus anthracis	ID
	Bordetella spp.	ID
	Brucella spp.	ID
	Burkholderia mallei	ID
	Burkholderia pseudomallei	ID
	Toxin-producing Corynebacterium -C. diptheriae, C. ulcerans, C. pseudotuberculosis	ID and AST^‡
	Cryptococcus neoformans	ID
	Francisella tularensis	ID
	Haemophilus influenzae	ID; β-lactamase
	Neisseria gonorrhoeae	ID
	Nocardia spp.	ID and AST
	Non-candida yeast	ID
	Non-saprophytic molds	ID
	Pseudomonas aeruginosa	ID and AST
	Stenotrophomonas maltophilia	ID and AST
	Streptococcus agalactiae (group B)- pediatric only	ID
	Streptococcus pneumoniae	ID and AST
	Streptococcus pyogenes (group A)	ID
	Yersinia pestis	ID
Significant 3+ for sputum, tracheal aspirates, BW 2+ for BAL 1+ for protected brushes	Burkholderia spp.	ID and AST
	Moraxella catarrhalis	ID; β-lactamase
	Staphylococcus aureus	ID and AST
Significant and predominant	Candida species	ID
	Enterococcus spp.	ID and AST
	Neisseria meningitidis	ID
	Non-pyogenes beta-hemolytic Streptococcus	ID
	Non-toxin producing Corynebacterium spp.	ID and AST^‡
	Single species of Gram-negative rod (not listed separately above)	ID and AST

^‡AST is not performed in house; isolate will be sent to reference lab for susceptibility testing