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Difficulty: MediumGastroenterology and Hepatology

Match each of the following Hepatitis B virus (HBV) serological profiles to the most appropriate clinical status. Interpret the profiles based on the presence (+) or absence (-) of specific viral markers.

  • HBsAg (+), Anti-HBc IgM (+), HBeAg (+), Anti-HBs (-)Acute hepatitis B infection
  • HBsAg (+), Anti-HBc IgG (+), HBeAg (-), Anti-HBs (-)Chronic hepatitis B infection with low infectivity
  • HBsAg (-), Anti-HBc IgG (+), HBeAg (-), Anti-HBs (+)Resolved prior hepatitis B infection
  • HBsAg (-), Anti-HBc (-), HBeAg (-), Anti-HBs (+)Immunity secondary to hepatitis B vaccination

Answer

The correct matches correlate acute infection with IgM anti-HBc, chronic infection with persistent HBsAg and IgG anti-HBc, resolved infection with both IgG anti-HBc and anti-HBs, and vaccination-induced immunity with anti-HBs alone.
Hepatitis B serology interpretation relies on the distinct combination of viral antigens and host antibodies. HBsAg is the primary marker of active infection. Anti-HBc IgM is the hallmark of acute infection, while Anti-HBc IgG denotes past exposure. Anti-HBs indicates systemic immunity. Finally, HBeAg serves as a surrogate marker for high viral replication and infectivity.

Step-by-Step Solution

1
Identify the marker of active infection.
Check for HBsAg. Profiles with HBsAg (+) represent active disease (acute or chronic).
HBsAg is the surface antigen and is the hallmark of an active, ongoing Hepatitis B infection.
2
Differentiate acute from chronic disease in the active infection profiles.
Evaluate Anti-HBc. The profile with IgM indicates acute infection, whereas the profile with IgG indicates chronic infection.
IgM antibodies against the core antigen are the first to appear and signify acute infection. IgG antibodies persist for life and, in the presence of continuous HBsAg, indicate a chronic carrier state.
3
Evaluate the profiles representing immunity.
Look at the profiles lacking HBsAg but containing Anti-HBs (+).
Anti-HBs is a neutralizing antibody that provides immunity to the virus. Its presence without HBsAg indicates the patient is immune.
4
Differentiate natural immunity from vaccination.
Examine Anti-HBc in the immune profiles. The profile with Anti-HBc IgG (+) represents prior natural infection. The profile with all negative markers except Anti-HBs represents vaccination.
Natural infection exposes the host to all viral components, leading to Anti-HBc IgG formation. The vaccine contains only recombinant surface antigen, so only Anti-HBs is produced.

Key Concept

Interpretation of Hepatitis B Serological Markers
Estimated Time:1m 30s
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Topics

Gastroenterology and Hepatology

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