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UW Health SMPH
American Family Children's Hospital

UW Hospital and Clinics Lab Test Directory

Test Name: AFB, Gastric Lavage

Test Code(s): AFB / HCAFB

CPT Code(s): 87015, 87206, 87116

Test Description: Test Component:

Acid fast stain and culture with identification for mycobacteria. Species identification may include HPLC, DNA probes, biochemical testing, growth characteristics, and gene sequencing.  Mycobacterial susceptibility available based on species isolated.

Methodology: Microscopy and Culture

Testing Site: Testing will be sent to an approved reference laboratory.

Days Performed: Mon-Fri.

Turnaround Time: Routine: Smear/Stain: 1 - 3 days. Final report: 1 - 8 weeks.

Specimen Requirements

Specimen: Gastric lavage

Collection Instructions: Collect fasting gastric lavage soon after patient awakens to obtain sputum swallowed during sleep. Immediately neutralize gastric lavage by placing in State Lab Gastric collection kit containing buffer. Obtain collection kit from UWHC Core Lab, (608)263-7060. Collect 3 specimens on DIFFERENT days.

Collection Container: Preferred: State Lab Gastric collection kit

Sample Analyzed: Gastric lavage

Volume Required: Preferred: 5 - 10 mL

Specimen Transport: Transport specimen to UWHC Core Laboratory (B4/220).
Transport to laboratory as soon as possible. Refrigerate if submission of specimen is delayed.

Unacceptable Criteria: Specimens that have not been neutralized (buffered) are not acceptable.


Additional Information:

Culture results include:  Negative; Species identification when mycobacterial growth is detected; Culture overgrown with non-acid fast organisms.


Mycobacterial susceptibility testing recommended for M. tuberculosis isolates.

Acid Fast Bacillus

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