A 30-year-old man presents with jaundice, right hypochondriac pain, and dark urine. Serology shows: HBsAg positive, Anti-HBc IgM positive, HBeAg positive, Anti-HBs negative, Anti-HBe negative, HBV DNA 2 × 10⁸ IU/mL, Anti-HCV negative. This pattern MOST likely represents:
- A Acute hepatitis B infection in the window period
- B Chronic hepatitis B, HBeAg-positive (immune tolerant phase)
- C Resolved hepatitis B with recent reactivation
- D Acute hepatitis B infection — early phase, high viral replication ✓
Explanation
The serological profile — HBsAg+, IgM anti-HBc+, HBeAg+, Anti-HBs−, Anti-HBe−, very high HBV DNA — is classic for acute hepatitis B in the early replication phase. IgM anti-HBc is the most reliable marker of acute HBV infection and is present before Anti-HBs appears. HBeAg positivity with very high DNA confirms active viral replication. The window period (when HBsAg disappears but Anti-HBs has not yet appeared) is characterized by HBsAg negative, IgM anti-HBc positive — this patient is still HBsAg positive. The immune tolerant phase of chronic HBV also has HBeAg+ and high DNA, but IgM anti-HBc would be negative; IgG anti-HBc would be positive.
Reference: Ananthanarayan & Paniker's Textbook of Microbiology, 11th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.