What are the initial steps for a hepatitis B (HBV) workup?

Initial Hepatitis B Workup

The initial hepatitis B workup should include serologic testing for HBsAg, anti-HBs, and anti-HBc, along with liver function tests, HBV DNA quantification, and HBeAg/anti-HBe to determine infection status and guide management. 1

Serologic Testing

Essential Serologic Markers

• HBsAg (Hepatitis B surface antigen): Primary marker for active infection; persistence beyond 6 months indicates chronic infection
• Anti-HBs (Antibody to HBsAg): Indicates immunity (from vaccination or resolved infection)
• Anti-HBc (Total core antibody): Indicates previous or ongoing HBV infection
• IgM anti-HBc: Marker for acute infection; detectable for approximately 6 months
• HBeAg/anti-HBe: Markers of viral replication status and infectivity

Interpretation of Serologic Results

• Acute HBV infection: HBsAg positive, IgM anti-HBc positive
• Chronic HBV infection: HBsAg positive for >6 months, total anti-HBc positive, IgM anti-HBc negative
• Resolved infection: HBsAg negative, anti-HBs positive, anti-HBc positive
• Vaccine-induced immunity: HBsAg negative, anti-HBs positive, anti-HBc negative
• Isolated anti-HBc: May indicate occult HBV infection, window period, or false positive

Laboratory Assessment

Liver Disease Assessment

• Complete blood count with platelets
• Liver function tests (AST, ALT, alkaline phosphatase, GGT, bilirubin)
• Albumin and prothrombin time (to assess synthetic function)
• Alpha-fetoprotein (baseline for HCC screening)

Viral Replication Assessment

• HBV DNA quantification (viral load)
• HBeAg/anti-HBe status

Coinfection Screening

• Anti-HCV (hepatitis C virus)
• Anti-HDV (hepatitis D virus) in high-risk individuals
• HIV testing in high-risk individuals
• IgG anti-HAV (to assess hepatitis A immunity) 1

Liver Disease Staging

• Non-invasive assessment of fibrosis (transient elastography/FibroScan if available)
• Liver biopsy may be considered in selected patients with elevated or fluctuating ALT levels to assess inflammation and fibrosis 1

Imaging

• Baseline ultrasound for all HBsAg-positive persons ≥20 years old to screen for hepatocellular carcinoma 1

Additional Considerations

Vaccination Status

• Check hepatitis A immunity (IgG anti-HAV) and vaccinate if non-immune
• Vaccinate household and sexual contacts against HBV if non-immune

Risk Factor Assessment

• Family history of HBV infection and HCC
• Alcohol consumption and drug use
• Risk factors for coinfections

Common Pitfalls to Avoid

1. Missing occult HBV infection: In patients with isolated anti-HBc, consider HBV DNA testing to rule out occult infection, especially in immunocompromised patients.

2. Misinterpreting the window period: During the window period between disappearance of HBsAg and appearance of anti-HBs, IgM anti-HBc may be the only detectable marker.

3. Failing to screen for coinfections: HBV patients should be screened for HDV, HCV, and HIV as appropriate based on risk factors.

4. Overlooking HCC surveillance: All chronic HBV patients need appropriate HCC surveillance, particularly those at higher risk (Asian men >40 years, Asian women >50 years, Africans >20 years, cirrhotics, and those with family history of HCC). 1

5. Neglecting hepatitis A vaccination: Hepatitis A vaccination is crucial as coinfection with HAV in HBV carriers increases mortality risk 5.6- to 29-fold. 1

By following this comprehensive approach to hepatitis B workup, clinicians can accurately diagnose the infection status, assess disease severity, and determine appropriate management strategies to reduce morbidity and mortality associated with chronic HBV infection.