What does an acute hepatitis panel check for?

Components of an Acute Hepatitis Panel

An acute hepatitis panel checks for serological markers of hepatitis A, B, and C viruses to diagnose acute viral hepatitis infections and distinguish them from chronic infections. The panel typically includes specific antibody and antigen tests that help identify the causative virus and stage of infection 1, 2.

Core Components of the Acute Hepatitis Panel

Hepatitis A Testing

• Anti-HAV IgM: Indicates acute hepatitis A infection
• Total Anti-HAV: Indicates past infection or immunity from vaccination

Hepatitis B Testing

• Hepatitis B Surface Antigen (HBsAg): Indicates active HBV infection (acute or chronic)
• Hepatitis B Core Antibody (Anti-HBc) IgM: Specifically indicates acute HBV infection
• Total Hepatitis B Core Antibody (Total Anti-HBc): Indicates past or current infection
• Hepatitis B Surface Antibody (Anti-HBs): Indicates immunity from past infection or vaccination

Hepatitis C Testing

• Hepatitis C Antibody (Anti-HCV): Indicates exposure to HCV
• HCV RNA: Confirmatory test if antibody is positive, distinguishes active from resolved infection

Interpretation of Results

For Hepatitis A

• Acute infection: Positive Anti-HAV IgM
• Past infection or immunity: Positive total Anti-HAV, negative Anti-HAV IgM

For Hepatitis B

• Acute infection: Positive HBsAg and positive Anti-HBc IgM
• Chronic infection: Positive HBsAg, positive total Anti-HBc, negative Anti-HBc IgM, HBsAg persisting >6 months 1
• Resolved infection: Negative HBsAg, positive Anti-HBc, positive Anti-HBs
• Vaccination immunity: Negative HBsAg, negative Anti-HBc, positive Anti-HBs

For Hepatitis C

• Exposure to HCV: Positive Anti-HCV
• Active infection: Positive Anti-HCV and positive HCV RNA
• Resolved infection: Positive Anti-HCV and negative HCV RNA

Additional Tests Often Included

Liver Function Tests

• Alanine aminotransferase (ALT) and Aspartate aminotransferase (AST): Elevated levels indicate liver cell damage 1
• Alkaline phosphatase: Evaluates biliary function
• Total and direct bilirubin: Elevated in jaundice
• Albumin: Assesses liver synthetic function
• Prothrombin time/INR: Evaluates coagulation status and liver synthetic function 1

Clinical Applications

1. Diagnosis of acute viral hepatitis: Distinguishes between hepatitis A, B, and C as the cause of acute liver inflammation 1, 2

2. Differentiation between acute and chronic infection: Particularly important for hepatitis B, where IgM anti-HBc indicates acute infection 1, 2

3. Monitoring of disease progression: Serial testing helps track the course of infection

4. Screening high-risk individuals: Identifies infections in asymptomatic individuals 1

Common Pitfalls in Interpretation

• Window period: During early infection, antibody tests may be negative despite active infection
• False negatives: May occur in immunocompromised patients who cannot mount an adequate antibody response 1
• Isolated Anti-HBc: May indicate occult hepatitis B, resolved infection, or false positive result 1
• Fluctuating ALT/AST: Levels may fluctuate during acute infection, so timing of testing is important 1

When to Order Additional Tests

• If initial panel is inconclusive but clinical suspicion remains high
• To evaluate for hepatitis D (only in HBsAg-positive patients)
• To evaluate for hepatitis E in patients with negative hepatitis A, B, and C tests but with elevated liver enzymes 3
• To quantify viral load (HBV DNA or HCV RNA) for treatment decisions 1

The acute hepatitis panel is a critical diagnostic tool that guides appropriate management and helps prevent complications of viral hepatitis, ultimately reducing morbidity and mortality from these infections.