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

Management of Reactive Hepatitis C Antibody Test Results

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

Testing Algorithm

Step 1: Confirm Current Infection Status

• A reactive HCV antibody test indicates one of three possibilities:

  1. Current HCV infection
  2. Past HCV infection that has resolved
  3. False positive result 1

• HCV RNA testing is mandatory to distinguish between these possibilities and should be performed on all patients with reactive antibody tests 1, 2

Step 2: Specimen Collection

• Ideally, use the same venipuncture blood sample for both antibody and RNA testing through reflex testing 1
• If using OraQuick HCV Rapid Antibody Test with fingerstick blood, collect a separate venipuncture sample for HCV RNA testing 1
• Single-visit sample collection is critical to avoid incomplete testing and loss to follow-up 2, 3

Step 3: Interpretation of Results

• If HCV RNA is detected: Patient has current HCV infection and should be referred for treatment evaluation 1, 4
• If HCV RNA is not detected: Patient either has resolved past infection or a false positive antibody test 1

Special Considerations

Recent Exposure

• For patients with possible HCV exposure within the past 6 months:
  • Consider repeat HCV RNA testing even if initial RNA test is negative
  • The antibody may not have developed yet in acute infection 1

Immunocompromised Patients

• Consider direct HCV RNA testing in immunocompromised patients
• These patients may have false-negative antibody results 4

Distinguishing False Positives from Resolved Infection

• If clinically important to differentiate between past resolved infection and false positive:
  • Test with a second, different HCV antibody assay 1
  • Consider signal-to-cutoff (S/CO) ratio - higher ratios are more likely to represent true positivity 5

Common Pitfalls to Avoid

1. Incomplete testing: Approximately one-third of patients historically have incomplete testing (no RNA test after reactive antibody) 2

   • Ensure automatic reflex testing is in place to prevent this 3

2. Loss to follow-up: Younger patients and people who inject drugs are less likely to be linked to care 6

   • Consider implementing robust follow-up procedures for these high-risk groups

3. Testing location impact: Patients diagnosed in outpatient settings are more likely to receive appropriate follow-up than those diagnosed in emergency departments or inpatient settings 7

   • Establish clear protocols for follow-up regardless of testing location

Next Steps After Diagnosis

For Patients with Confirmed Current Infection

• Report positive results to health departments as required by local regulations 1
• Refer for specialist evaluation for treatment consideration
• Educate patients about:
  • Limiting disease progression (avoiding alcohol, vaccination against hepatitis A and B)
  • Preventing transmission to others 1
• Test for HBV coinfection (HBsAg and anti-HBc) before starting treatment to prevent HBV reactivation 8, 9

For Patients with Resolved Infection or False Positives

• Inform patients they are not currently infected and not infectious to others 1
• Consider risk factors for reinfection and provide appropriate counseling

By following this evidence-based approach to reactive HCV antibody tests, clinicians can ensure proper diagnosis, reduce loss to follow-up, and improve patient outcomes through timely treatment of current infections.