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Hepatitis Be Surface Antigen and Antibody General
Clinical Tests
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Test Name
Method |
Hepatitis Be Antigen and Antibody, (HBeAg; Anti-HBe, HBeAb)
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Specimen
Requirements |
Serum
Stable for 7 d at RT and indefinitely at 4° C or - 20°C. |
Ref. Range
Conventional
International Recommended Units |
Negative |
Chemical Interfaces
In Vivo Effects |
None Found
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| Diagnostic Information |
HBeAg and anti-HBe are ordered together and should only be studied in
patients who are chronicially HBsAg postive. There is no rationale for ordering
these studies in patients with acute hepatitis. HBeAg is related to Hepatitis
B core protein but has different antigenicity. The HBe gene includes the
HBc gene along with an upstream "preC" region that generates a signal peptide
causing carboxy-terminal truncation of the core protein. The resulting HBeAg
is not incorporated into virus buy may function to induce host immune tolerance.
In general, active Hepatitis B viral replication is associated with infective
serum that is HBeAg postive and anti-HBe negative. Upon conversion to a
nonreplicative state, anti-HBe appears in the serum and HBeAg disappears.
The main utility of testing for HBeAg and anti-HBe is to assess response
of the Hepatitis B infection to therapy such as interferon-a.
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| Remarks |
Presence of HBeAg implies the infective Hepatitis B virus is present in
the serum. However, its absence upon conversion to anti-HBe does not rule
out infectivity. Measurement of HBV-DNA directly is now recommended. |
References:
Clinical Guide to Laboratory Tests, third edition.
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