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UW Health SMPH
American Family Children's Hospital

UW Hospital and Clinics Lab Test Directory

Test Name: Culture, Sputum, CF Patient

Test Code(s): CFC / HCCFC, CFCS / HCCFCS

CPT Code(s): 87070, 87205; Additional CPT codes may be added for processing, identification, and susceptibility testing.

Test Description: Test Component:

Culture and Gram stain

Methodology: Culture, Microscopy

Clinical Significance: Individuals with cystic fibrosis experience recurrent lower respiratory tract infections for their entire lives. The infecting organisms change with the age of the patient, mixed infections are common, and the presence of Burkholderia cepacia group has an impact on prognosis and, perhaps, lung transplant eligibility. Special microbiological media are used to assure isolation of all significant pathogens. Exacerbations are treated with antibiotics and development of antimicrobial resistance is common. For all of these reasons, cultures and susceptibility testing are routinely performed quarterly on outpatients and on each admission to hospital.

Days Performed: Daily, 24 hours.

Turnaround Time: Routine: Preliminary report: 24 hours. Cultures with no growth or endogenous flora will be reported after 48 hours. Reports on specimens from which pathogens are isolated require a minimum of 48 hours for completion.

Specimen Requirements

Specimen: Expectorated, suctioned or induced sputum, tracheal aspirate, cough throat swabs on pediatric patients

Collection Container: Preferred: Sterile screw cap container
Also Acceptable: CultureSwab®

Specimen Transport: Transport specimen to UWHC Microbiology (B4/231) within 2 hours of collection.

Unacceptable Criteria: More than one specimen received from the same patient within 24 hours is not acceptable.

Stability: Ambient: 2 hours
Refrigerated: 24 hours
Frozen: Not acceptable


Expected Results:

Endogenous respiratory flora

Test Limitations:

Since expectorated sputum, tracheal aspirations, and most bronchial washings are contaminated with endogenous oropharyngeal flora (which includes most of the common lower respiratory tract pathogens), cultures of such specimens are neither particularly sensitive nor specific for the diagnosis of bacterial pneumonia and results should be interpreted with caution. Blood cultures are recommended for the diagnosis of pneumonia, especially for hospitalized patients and those with severe community acquired pneumonia (CAP).

Additional Information:

Susceptibility testing is performed based on lab protocols.


Special methods are necessary for detection of mycobacteria, Legionella, filamentous and dimorphic fungi, Nocardia, and Mycoplasma. See individual entries for additional information. 

cystic fibrosis

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