Louisiana Department of Health & Hospitals | Kathy Kliebert, Secretary

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Hepatitis B Surface Antigen Confirmatory

Hepatitis B Surface Antigen Confirmatory

  • Laboratory Location – Central Laboratory
  • CPT Code – 87341
  • Synonyms – HBsAg Confirmatory
  • Test Description - The Genetic Systems (GS) HBSAg Confirmatory Assay 3.0 is a qualitative assay intended for the confirmation of HBsAg reactive specimens detected in the GS HBsAg EIA 3.0.

Possible Results

  • Negative
  • Positive
  • Not confirmed

Reference Range

  • Negative

Specimen Requirements

  • Specimen Type - Serum
  • Specimen Container(s) - red top tubes, Marble top tubes, polypropylene vials
  • Minumum accepted volume - 760 μL

Specimen Collection Instructions

Blood should be collected in a plastic, sterile STD Program approved collection tube. Please follow the manufacturer's instructions on clot time and centrifuge speed/time requirements.

The Virology Lab 96 form must be filled out completely. The following information must be included on the form:

  • Patient's Name
  • Patient's Date of Birth
  • Patient's Gender
  • Date and time of specimen collection
  • Test requested
  • Type of specimen collected
  • Submitter's name and address

Storage and Transport Instructions

Specimens should be shipped refrigerated (2-8ºC) or at ambient temperatures for up to 7 days. For longer storage, specimens must be frozen at -20ºC or colder. Frozen specimens must be shipped on dry ice and received at a temperature of -20ºC or colder.

Causes for Rejection

  • expired collection tubes
  • incorrect specimen type
  • unspun samples
  • tubes that contain less than 90% of the total drawing capacity (QNS)
  • Improper storage or improper transport temperature requirements are also reasons for rejection

Limitations for the Procedure

The package insert must be strictly adhered to when testing serum for the presence of HBsAg. False negative results can occur if the quantity of marker present in the samples is too low for the detection limits of the assay, or if the marker which is detected is not present during the stage of disease in which a sample is collected. Failure to add specimen or reagent as instructed in the procedure could result in a falsely negative test.

Interfering Substances

  • No clinically significant effect has been detected in assay results with increased levels of protein, lipids, bilirubin, or hemolysis, or after heat inactivation of patient samples.


  • BioRad Genetic Systems HBsAg EIA 3.0 package insert
  • EVOLISTM Operator Manual

Additional Information

  • Negtaive - Specimen Confirmed Negative for Hepatitis B Surface Antigen
  • Positive - Specimen Confirmed Positive for Hepatitis B Surface Antigen
  • Not Confirmed - The Presence or Absence of Hepatitis B Surface Antigen was Not Confirmable

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