What tests are recommended for follow-up after a positive Hepatitis B core antibody (HepbCAb) and Hepatitis B surface antibody (HepbSab) result?

Follow-up Testing for Positive Hepatitis B Core Antibody (HBcAb) and Surface Antibody (HBsAb)

For a patient with positive HBcAb and HBsAb results, HBV DNA testing is recommended to rule out occult hepatitis B infection, along with liver function tests to assess for any liver damage.

Interpretation of Current Serological Status

The combination of positive hepatitis B core antibody (HBcAb) and positive hepatitis B surface antibody (HBsAb) typically indicates:

• Resolved past HBV infection with natural immunity - The most common interpretation 1
• The presence of anti-HBs (HBsAb) generally indicates protection against HBV infection

However, this serological pattern requires further evaluation to:

1. Confirm complete resolution of infection
2. Rule out occult hepatitis B infection (OBI)
3. Assess for any liver damage

Recommended Follow-up Testing

Immediate Testing

1. HBV DNA quantification test 2

   • Critical to rule out occult HBV infection, which can occur in 1-20% of anti-HBc positive individuals
   • Particularly important before any immunosuppressive therapy

2. Liver function tests 2, 3

   • Complete blood count
   • AST/ALT (transaminases)
   • Alkaline phosphatase
   • Gamma-glutamyl transpeptidase
   • Bilirubin
   • Albumin
   • Prothrombin time

3. HBeAg and anti-HBe testing 2

   • To further characterize the HBV infection status

4. Tests for coinfections 2

   • Anti-HCV (hepatitis C virus)
   • Anti-HDV (hepatitis D virus) - particularly important in patients with a history of drug abuse
   • Anti-HIV in high-risk groups

Additional Considerations

• Ultrasound examination may be indicated if liver function tests are abnormal 3
• Liver biopsy is generally not required with this serological pattern unless there are signs of active liver disease 2

Long-term Monitoring

• If all follow-up tests are normal (negative HBV DNA, normal liver function):

  • No specific ongoing monitoring is required for the HBV infection itself 1
  • Regular liver function monitoring may be considered every 6-12 months, particularly in patients with other risk factors for liver disease

• If HBV DNA is detected (occult HBV infection):

  • More intensive monitoring is required
  • Consider referral to a hepatologist for management 2

Special Considerations

Before Immunosuppressive Therapy

• Patients who will undergo immunosuppressive therapy, particularly with anti-CD20 antibodies, require:
  • HBV DNA testing to rule out occult infection 2
  • Prophylactic antiviral therapy may be needed even with this serological pattern 2, 1
  • Hepatology consultation is strongly recommended 2

Screening of Close Contacts

• Household members and sexual partners should be screened for HBV (HBsAg and anti-HBs) 1
• Those who test negative should receive hepatitis B vaccination 1

Hepatitis A Immunity

• Test for hepatitis A immunity (anti-HAV) 2
• Vaccinate against hepatitis A if not immune, as coinfection with hepatitis A in HBV carriers increases mortality risk 2

Common Pitfalls to Avoid

1. Assuming complete resolution without HBV DNA testing - Occult HBV infection can exist despite positive anti-HBs
2. Neglecting to screen close contacts - Important for prevention
3. Missing the opportunity to vaccinate against hepatitis A - Critical to prevent additional liver damage
4. Failing to consider prophylactic therapy before immunosuppression - Can lead to HBV reactivation

By following these recommendations, clinicians can ensure appropriate management of patients with positive HBcAb and HBsAb results, preventing complications and ensuring optimal outcomes.