What is the next step for a patient with a reactive Hepatitis C (Hep C) antibody test?

Management of Reactive Hepatitis C Antibody Test

For patients with a reactive Hepatitis C (HCV) antibody test, the next step is to perform HCV RNA testing to confirm current infection. 1

Testing Algorithm

1. Initial positive anti-HCV antibody test

   • A reactive HCV antibody test indicates one of three possibilities:
     • Current HCV infection
     • Past, resolved HCV infection
     • False positive result 1

2. HCV RNA testing (mandatory next step)

   • Nucleic Acid Testing (NAT) for HCV RNA is required to determine if active infection is present
   • This distinguishes between current infection and resolved/false positive results 1
   • Several operational approaches are possible:
     • Use the same blood sample (reflex testing)
     • Collect a second specimen at the same time as initial antibody testing
     • Request a subsequent venipuncture 1

3. Interpretation of HCV RNA results:

   • Positive HCV RNA: Confirms current HCV infection
   • Negative HCV RNA: Indicates either resolved infection or false positive antibody test 1

Special Considerations

• Recent exposure: For patients with possible HCV exposure within the past 6 months, HCV RNA testing is especially important as antibodies may not have developed yet 1

• Immunocompromised patients: Consider direct HCV RNA testing as these patients may have false-negative antibody results 1, 2

• Distinguishing resolved infection from false positivity: If clinically important, testing with a second, different HCV antibody assay can be considered 1

Follow-up Actions

• For HCV RNA positive patients:

  • Prompt referral for specialist evaluation and treatment to prevent disease progression 2
  • Assess for liver fibrosis to determine treatment urgency 3
  • Test for HBV coinfection (HBsAg and anti-HBc) before initiating treatment 4, 5
  • Consider testing for HCV genotype to guide treatment decisions 3

• For HCV RNA negative patients with positive antibody:

  • No further immediate action required for the HCV infection
  • Consider repeat HCV RNA testing if clinical suspicion remains high or recent exposure is suspected 1

Common Pitfalls to Avoid

• Not testing for HBV coinfection: HBV reactivation can occur during HCV treatment, potentially resulting in fulminant hepatitis, liver failure, and death 4, 5

• Missing acute infection: In early infection, HCV RNA may be detectable before antibodies develop 1

• Incomplete follow-up: Ensuring patients with confirmed HCV infection receive appropriate evaluation and treatment is critical to prevent progression to cirrhosis and hepatocellular carcinoma 6

• Relying solely on antibody testing: A reactive antibody test alone cannot distinguish between current infection, resolved infection, or false positive results 1

By following this evidence-based approach to managing patients with reactive HCV antibody tests, you can ensure accurate diagnosis and appropriate care to reduce morbidity and mortality from HCV infection.