What is the approach to evaluating and managing chronic hepatitis B?

Evaluation and Management of Chronic Hepatitis B

The comprehensive evaluation of chronic hepatitis B requires serologic testing, liver function assessment, viral load quantification, and fibrosis assessment to determine disease activity and guide management decisions. 1

Diagnostic Criteria

• Chronic hepatitis B definition: HBsAg positivity for >6 months with:

  • HBeAg-positive CHB: HBV DNA ≥20,000 IU/mL with persistent/intermittent ALT elevation
  • HBeAg-negative CHB: HBV DNA ≥2,000 IU/mL with persistent/intermittent ALT elevation 2

• Inactive HBV carrier state: HBsAg positivity for >6 months, HBeAg negativity, anti-HBe positivity, HBV DNA <2,000 IU/mL, and persistently normal ALT levels 2

Initial Evaluation

Laboratory Assessment

1. Liver function tests: Complete blood count, AST/ALT, alkaline phosphatase, gamma-glutamyl transpeptidase, bilirubin, albumin, creatinine, and prothrombin time 2, 1

2. Serologic markers for HBV replication:

   • HBsAg/anti-HBs
   • HBeAg/anti-HBe
   • HBV DNA quantification 2, 1

3. Tests for coinfections:

   • Anti-HCV
   • Anti-HDV (especially in persons with history of drug abuse)
   • Anti-HIV (in high-risk groups) 2

4. Immunity assessment:

   • IgG anti-HAV (for vaccination consideration) 2

Imaging and Fibrosis Assessment

1. Abdominal ultrasound: To assess for cirrhosis and screen for HCC 2, 1

2. Liver biopsy: Consider when:

   • ALT and HBV DNA results are discordant
   • To assess inflammation grade and fibrosis stage
   • To rule out other causes of liver disease 2

3. Non-invasive fibrosis assessment:

   • Transient elastography (FibroScan) can be considered 1

HCC Screening

• Baseline alpha-fetoprotein (AFP) and ultrasound for patients at risk of HCC:
  • Asian men >40 years
  • Asian women >50 years
  • Persons with cirrhosis
  • Persons with family history of HCC
  • Africans >20 years
  • HBV-infected persons >40 years with persistent/intermittent ALT elevation 2

Patient Classification and Monitoring

HBeAg-Positive Patients with High HBV DNA but Normal ALT

• Monitor every 3-6 months
• Liver biopsy generally not necessary unless treatment is contemplated
• More frequent monitoring when ALT becomes elevated 2
• Consider liver biopsy and antiviral treatment if HBeAg positive with HBV DNA >10^5 copies/mL after 3-6 months of elevated ALT 2

HBeAg-Positive Patients with Elevated ALT

• May observe for 3-6 months for spontaneous HBeAg seroconversion before initiating treatment 2
• If no spontaneous seroconversion occurs, consider antiviral therapy 2

Inactive HBsAg Carriers

• Monitor with periodic liver biochemistries as liver disease may become active even after years of quiescence 2
• Monitor every 3 months for 1 year; if persistently normal, every 6-12 months thereafter 1

Counseling and Prevention

• Lifestyle modifications:

  • Avoid or limit alcohol consumption (heavy use of alcohol >40g/day associated with higher ALT levels and cirrhosis development) 2
  • No specific dietary measures have proven effect on CHB progression 2

• Transmission prevention:

  • Clean blood spills with bleach solution
  • Refrain from donating blood, plasma, tissue, or semen
  • Avoid sharing household items that could be contaminated with blood (toothbrushes, razors)
  • Dispose of blood and medical waste properly 2

• Vaccination:

  • Vaccinate household members who test negative for HBV serologic markers 2
  • Vaccinate against hepatitis A (2 doses, 6-18 months apart) if chronic liver disease is present 2

Common Pitfalls to Avoid

1. Do not rely solely on ALT/AST levels - they may be normal in some patients with chronic hepatitis B 1

2. Do not overlook testing for HDV in HBsAg-positive patients, especially those with risk factors 1

3. Do not miss isolated anti-HBc - may indicate occult HBV infection requiring HBV DNA testing 1

4. Do not forget HCC surveillance in high-risk patients with chronic hepatitis B 1

5. Do not use inadequate HBV DNA assays - modern real-time PCR assays with sensitivity of 5-10 IU/ml and wide dynamic range are recommended 1

By following this structured approach to evaluation and management, clinicians can effectively assess disease activity, determine appropriate monitoring intervals, and identify candidates for antiviral therapy to reduce morbidity and mortality from chronic hepatitis B.