**Question:** A 30 year old patient presented with history of jaundice for 10 days. His liver function tests showed bilirubin of 10 mg/dl, SGOT/SGPT - 1100/1450, serum alkaline phosphatase -240 IU. He was positive for HBsAg. What should be the confirmatory test to establish acute hepatitis B infection -

A. HBeAg
B. HBsAg
C. Anti-HBc
D. HBeAg and Anti-HBe

**Correct Answer:** D. HBeAg and Anti-HBe

**Core Concept:**
The correct answer is D due to the following reasons:

**Why the Correct Answer is Right:** Confirming the acute hepatitis B infection involves establishing the presence of both HBeAg and Anti-HBe antibodies. In the context of this question, the patient has a positive HBsAg, indicating a current HBV infection. The presence of HBeAg indicates active viral replication and is associated with high viral load and high risk of progression to chronic hepatitis B infection. Anti-HBe antibody is produced in response to the HBeAg and indicates a transition from the active phase of the infection to the inactive carrier state, where the viral load decreases and the disease is less likely to progress to chronicity.

**Why Each Wrong Option is Incorrect:**

**A. HBeAg:**
HBeAg is present during the active phase of the infection, representing high viral load, and is associated with high risk of progression to chronic hepatitis B infection. Its absence does not rule out acute hepatitis B, but indicates a transition from the active phase to the inactive carrier state.

**B. HBsAg:**
HBsAg is present in acute, chronic, and resolved hepatitis B infections, indicating a current HBV infection but does not provide information about the progression of the infection.

**C. Anti-HBc:**
Anti-HBc is a marker of past hepatitis B infection, indicating exposure to HBV. It is not specific for acute hepatitis B and is not sufficient to confirm the active infection.

**D. HBeAg and Anti-HBe:**
As explained above, this combination confirms the active phase of acute hepatitis B infection (HBeAg) and the transition to the inactive carrier state (Anti-HBe). This combination is essential for confirming acute hepatitis B.

**Clinical Pearl:**
Understanding the significance of HBsAg, HBeAg, and Anti-HBe is crucial for diagnosing acute hepatitis B infection. The combination of HBsAg and Anti-HBe is essential for confirming acute hepatitis B infection. The presence of HBeAg indicates active viral replication, while the presence of Anti-HBe suggests the transition from active phase to the inactive carrier state.