Examkin

Question

Difficulty: MediumGastroenterology and Hepatology

Match each patient's clinical presentation and Hepatitis B serologic profile to their most appropriate diagnosis or immune status.

  • A 25-year-old medical student evaluated prior to clinical rotations. Serology shows HBsAg negative, Anti-HBs positive, and Anti-HBc negative.Immunity secondary to vaccination
  • A 45-year-old man undergoing a routine physical examination. Serology shows HBsAg negative, Anti-HBs positive, and Anti-HBc positive (IgG).Immunity secondary to resolved natural infection
  • A 50-year-old asymptomatic man from an endemic region. Serology shows HBsAg positive, Anti-HBs negative, and Anti-HBc positive (IgG).Chronic Hepatitis B infection
  • A 28-year-old woman presenting with new-onset jaundice, right upper quadrant discomfort, and fatigue. Serology shows HBsAg positive, Anti-HBs negative, and Anti-HBc positive (IgM).Acute Hepatitis B infection

Answer

The medical student (left_1) has vaccination immunity. The 45-year-old man (left_2) has natural immunity. The 50-year-old man (left_3) has chronic Hepatitis B. The 28-year-old woman (left_4) has acute Hepatitis B.
Hepatitis B serology interpretation is systematically based on three main markers. HBsAg represents the presence of the virus. Anti-HBs represents neutralizing immunity. Anti-HBc represents exposure to the actual virus (since the vaccine lacks the core). Vaccination yields isolated Anti-HBs. Cleared natural infection yields both Anti-HBs and Anti-HBc. Chronic infection maintains HBsAg and Anti-HBc (IgG) without forming Anti-HBs. Acute infection presents with HBsAg and an early Anti-HBc (IgM) response.

Step-by-Step Solution

1
Evaluate the first patient's serology (left_1).
HBsAg(-), Anti-HBs(+), Anti-HBc(-).
Since Anti-HBc is negative, the patient was never exposed to the full virus. Positive Anti-HBs indicates immunity from the recombinant surface antigen vaccine.
2
Evaluate the second patient's serology (left_2).
HBsAg(-), Anti-HBs(+), Anti-HBc IgG(+).
Positive Anti-HBc IgG shows prior infection with the live virus. Positive Anti-HBs and negative HBsAg show successful viral clearance and resulting natural immunity.
3
Evaluate the third patient's serology (left_3).
HBsAg(+), Anti-HBs(-), Anti-HBc IgG(+).
Presence of HBsAg indicates active virus. Positive Anti-HBc IgG (rather than IgM) and lack of acute symptoms point to a chronic carrier state.
4
Evaluate the fourth patient's serology (left_4).
HBsAg(+), Anti-HBs(-), Anti-HBc IgM(+).
HBsAg presence confirms infection, and the IgM class of Anti-HBc signifies that the infection is in the early, acute phase, matching the clinical presentation of jaundice.

Key Concept

Interpretation of Hepatitis B serological markers
Rate this question

Topics

Gastroenterology and Hepatology

More questions from this topic