What is the recommended approach for ordering Hepatitis C (HCV) and Human Immunodeficiency Virus (HIV) testing?

Recommended Approach for Ordering Hepatitis C and HIV Testing

For optimal detection of HCV and HIV infections, initial screening should be performed using an FDA-approved antibody test for HCV and HIV, with positive HCV antibody results confirmed by nucleic acid testing (NAT) for HCV RNA. 1

Testing Recommendations by Population

Universal Screening

• All adults should receive one-time HCV antibody testing, with special focus on:
  • Persons born between 1945-1965 (Baby Boomers) 1
  • All persons at initial HIV care entry 1

Risk-Based Screening

• Annual HCV testing is recommended for:

  • Persons who inject drugs 1
  • HIV-positive men who have sex with men (MSM) 1
  • Other persons with ongoing HCV exposure risk 1

• HIV testing should be performed:

  • For all HCV-infected individuals 1
  • For all persons entering care for sexually transmitted infections 2

Testing Sequence and Methods

For HCV Testing:

1. Initial test: Anti-HCV antibody using FDA-approved test 1
2. Confirmatory test: If antibody positive, order HCV RNA test (NAT) to confirm active infection 1
   • A positive RNA test indicates active infection requiring evaluation for treatment
   • A negative RNA test with positive antibody indicates resolved infection

For HIV Testing:

1. Initial test: HIV antibody/antigen test
2. Confirmatory testing per local laboratory protocols for positive results

Special Considerations

• Point-of-care testing or dried blood spot testing can be valuable alternatives for populations with difficult venous access 1
• For persons at high risk of reinfection (e.g., active injection drug users), consider testing every 6 months 1
• In HIV clinics, electronic medical record-based clinical decision support tools can help identify patients needing HCV testing 3

Testing in Special Populations

• HIV-positive patients: Screen for HCV at entry into care and annually if risk factors present 1
• Persons who inject drugs: Test for both HIV and HCV at least annually 1
• Pregnant women: Test for both HIV and HCV during pregnancy
• STI clinic attendees: Consider routine HCV testing for HIV-positive or HIV-unknown status MSM 2

Interpreting Results

• HCV antibody positive + HCV RNA positive: Active HCV infection requiring medical evaluation 1
• HCV antibody positive + HCV RNA negative: Previous HCV infection that has resolved 1
• HCV antibody negative: No HCV infection (unless recent exposure within window period)

Common Pitfalls to Avoid

• Failing to confirm positive HCV antibody tests with RNA testing
• Missing HCV infections in HIV-positive patients by not performing regular screening
• Using ALT elevation alone to trigger HCV testing (can miss cases with normal ALT)
• Relying on patient-reported risk factors, which may underestimate actual risk 4

Early detection of both HIV and HCV is crucial for improving patient outcomes through timely treatment initiation, preventing disease progression, and reducing transmission risk 1, 5.