Hepatitis B Surface Antibody, Qualitative
UFHPL Epic order code: LAB2107243
Anti-HBs usually can be detected several weeks to several months after HBsAg is no longer found, and it may persist for many years or for life after acute infection has been resolved. It may disappear in some patients, with only antibody to core remaining. Patients with this antibody are not overtly infectious. Presence of the antibody without the presence of the antigen is evidence for immunity from reinfection, with virus of the same subtype (vide supra). Anti-HBs can be induced by vaccination with hepatitis vaccine, now genetically engineered and free of any infective material. This vaccine so far has been safe and effective in protecting recipients from acute hepatitis B.
Type: Serum or plasma
Container/Tube: Red-top tube, gel-barrier tube or lavender-top tube (EDTA)
- If a tube other than a gel-barrier tube is used, transfer the separated serum to a plastic transport tube.
Sample Volume: 0.5 mL
Minimum Volume: 0.3 mL (Repeat testing is not possible with this specimen volume.)
Storage: Refrigerate specimens immediately after collection.
Stability (collection to time of analysis/testing):
- Ambient: 14 days
- Refrigerated: 14 days
- Frozen: 14 days
- Freeze/Thaw Cycles: Stable (x 3)
- Cadaver specimens
- Heat-inactivated specimens
- Body fluids other than serum or plasma
The presence of hepatitis B antibodies is an indicator of clinical recovery and subsequent immunity to hepatitis B virus. This test is useful for the evaluation of possible immunity in individuals who are at increased risks for exposure to the hepatitis B (e.g., hemodialysis unit personnel, venipuncturists, etc). Evaluate the need for hepatitis B immune globulin after needlestick injury; evaluate the need for hepatitis B vaccine and follow immune status after hepatitis B vaccine.
Presence of hepatitis B antibodies is not an absolute indicator of resolved hepatitis infection, nor of protection from future infection. Since there are different serologic subtypes of hepatitis B virus, it is possible (and has been reported) for a patient to have antibody to one surface antigen type and to be acutely infected with virus of a different subtype. Thus, a patient may have coexisting HBsAg and hepatitis B antibodies. Transfused individuals or hemophiliacs receiving plasma components may give false-positive tests for antibody to hepatitis B surface antigen.
Immunochemiluminometric assay (ICMA)
- Nonreactive: Inconsistent with immunity
- Reactive: Consistent with immunity
Monday - Friday