What tests are used for the evaluation of chronic hepatitis B?

Comprehensive Laboratory Tests for Chronic Hepatitis B Evaluation

The evaluation of chronic hepatitis B requires a comprehensive panel of serologic markers, liver function tests, viral load assessment, and imaging studies to determine disease activity, severity, and guide management decisions. 1, 2

Initial Serologic Testing

• HBV Serologic Markers:

  • HBsAg and anti-HBs: Fundamental tests to establish chronic infection (HBsAg positive for >6 months) 1
  • HBeAg and anti-HBe: Essential for determining phase of infection and replication status 1
  • Total and IgM anti-HBc: Helps differentiate between acute and chronic infection 1, 2

• HBV DNA Quantification:

  • Crucial for assessing viral replication, determining disease phase, and making treatment decisions 1
  • Modern real-time PCR assays with sensitivity of 5-10 IU/ml and wide dynamic range (up to 8-9 log10 IU/ml) are preferred 1

Liver Disease Assessment

• Liver Function Tests:

  • Complete blood count with platelets
  • Hepatic panel (ALT, AST, GGT, alkaline phosphatase)
  • Bilirubin (total and direct)
  • Albumin and prothrombin time/INR 1, 2

• Imaging:

  • Abdominal ultrasound to assess for cirrhosis and exclude focal lesions 1, 3
  • Consider transient elastography (FibroScan) for non-invasive assessment of fibrosis 1

• Liver Biopsy:

  • Consider for patients with inconclusive biochemical and HBV markers 1
  • Particularly useful when ALT/HBV DNA results don't clearly indicate disease activity 1
  • Helps grade inflammation and stage fibrosis to guide treatment decisions 1

Coinfection Screening

• Test for viral coinfections:
  • Anti-HCV (hepatitis C virus)
  • Anti-HDV (hepatitis D virus) - particularly important in those from endemic areas or with history of injection drug use
  • Anti-HIV in those at risk 1, 2
  • Anti-HAV (consider vaccination if negative) 1

Additional Testing

• Alpha-fetoprotein (AFP): Baseline screening for hepatocellular carcinoma in high-risk patients 1, 2
• HBV genotype: May be useful if interferon therapy is being considered 1
• HBsAg quantification: Useful for HBeAg-negative chronic infection and patients being considered for interferon therapy 1

Disease Phase Classification

Based on test results, patients can be classified into different phases:

1. Immune tolerant phase: HBeAg-positive, high HBV DNA, normal ALT
2. Immune active/chronic hepatitis phase: HBeAg-positive or negative, high HBV DNA, elevated ALT
3. Inactive carrier state: HBeAg-negative, anti-HBe positive, low/undetectable HBV DNA, normal ALT 1

Common Pitfalls to Avoid

• Don't rely solely on ALT levels - they may be normal despite significant liver disease 2
• Don't overlook HDV coinfection - test all HBsAg-positive patients from endemic areas 2
• Don't use arbitrary HBV DNA cutoffs - serial monitoring is more important than single values 1
• Don't miss occult HBV infection - consider HBV DNA testing in isolated anti-HBc positive patients 2

Monitoring Recommendations

For patients not immediately requiring treatment:

• HBeAg-positive with normal ALT: Monitor ALT every 3-6 months; more frequently if ALT becomes elevated 1
• Inactive HBsAg carrier: Monitor ALT every 3 months for 1 year; if persistently normal, every 6-12 months thereafter 1
• All chronic HBV patients: Consider regular HCC surveillance with ultrasound ± AFP in relevant populations 1