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UW Health SMPH
American Family Children's Hospital

UW Hospital and Clinics Lab Test Directory

Test Name: Hepatitis B Surface Ag

Test Code(s): HBSA / HBSAG

CPT Code(s): 87340

Methodology: Chemiluminescent Immunoassay

Clinical Significance: Detects surface antigen of Hepatitis B.

Days Performed: Mon-Fri, dayshift.

Turnaround Time: Stat: Not available stat.
Routine: Next working day.

Specimen Requirements

Specimen: Blood

Collection Container: Preferred: Red cap with yellow ring (SST)
Also Acceptable: Red top

Collection Volume: Preferred: 4 mL
Pediatrics: 3 mL

Sample Analyzed: Serum

Volume Required: Preferred: 2 mL
Pediatrics: 1.3 mL

Specimen Processing: Centrifuge.  If complete barrier is not formed, transfer cell-free serum to plastic vial.  Refrigerate.

Specimen Transport: Transport specimen to UWHC Core Laboratory (B4/220). Transport with coolant pack if coming from outreach location.

Stability: Ambient: 8 hours
Refrigerated: 7 days
Frozen: >14 days


Reference Interval:



Interpretation of Hepatitis B Test Result.pdf

Test Limitations:

Results may be affected if patient has developed heterophilic antibodies due to exposure to animal based protein products.


The assay performance characteristics have not been established for immunocompromised or immunosuppressed patients, newborns, infants or children, cord blood, neonatal specimens, cadaver specimens, heat inactivated specimens and body fluids other than serum.


This method is approved for diagnostic testing only.  It is not approved for screening tissue donors that fall under FDA's HCT/P requirements.


Additional Information:

All reactive specimens are tested by a neutralizing confirmatory assay.


If HBcAb and HBsAg are positive with a negative HBsAb, a Hepatitis B Core Ab IgM is recommended.  If HBsAb and HBsAg are negative with a positive HBcAb, then Hepatitis B Viral DNA testing may aid in the interpretation of results.

HBsAg hep b

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