Test Code HBSAG Hepatitis B Surface Antigen (HBsAg) [LAB471]
Test Method
Electrochemiluminescence sandwich principle: Roche cobas Pro
Performance
Testing is performed 7 days a week Monday through Sunday. Routine specimen requests are completed the same day upon arrival to the laboratory. Stat requests are completed within 4 hours upon receipt.
Useful For
The hepatitis B surface antigen, a polypeptide of varying size, is a component of the external envelope of the hepatitis B virus particle (HBV). The blood of persons infected with HBV contains, in addition to intact infectious HBV particles, smaller non-infectious “empty” envelope particles, which are formed in great excess and also contain the hepatitis B surface antigen. The detection of HBsAg in human serum or plasma indicates an infection by the hepatitis B virus. HBsAg is the first immunological marker to appear in acute hepatitis B infection and is generally present some days or weeks before clinical symptoms begin to appear. HBsAg is observed in persons with acute and chronic hepatitis B infections. HBsAg tests are part of the diagnostic algorithm used to identify persons infected with HBV and to prevent the transmission of the hepatitis B virus by blood and blood products.
Reference Values
Nonreactive
Performing Laboratory
UnityPoint The Finley Hospital
Specimen Requirements
- Serum is the specimen of choice.
- Lithium heparin and EDTA plasma are also acceptable sample types; however, serum is required if confirmation testing is needed.
- Gel tubes are acceptable.
- Hepatitis B Surface Antigen specimens are stable for 6 days at 20-25°C, 14 days at 2-8°C, and 6 months at -20°C.