What are the implications for a pregnant patient with Hepatitis C (Hep C) antibody positive but RNA negative?

Hepatitis C Antibody Positive with RNA Negative in Pregnancy: Implications

A pregnant patient with positive Hepatitis C antibody but negative RNA testing indicates a resolved HCV infection or a false positive result, not an active infection. 1

Understanding the Results

When a pregnant patient tests positive for HCV antibodies but negative for HCV RNA, there are two possible interpretations:

1. Resolved Infection: The patient had HCV infection in the past that has spontaneously cleared (approximately 20% of all HCV infections resolve without treatment) 1
2. False Positive Result: The initial antibody test was a false positive

Confirming the Interpretation

To distinguish between these two possibilities:

• Re-test for HCV antibodies using a different antibody assay platform (such as PCR or immunoblot) 1
  • If the second antibody test is negative → Initial test was a false positive
  • If the second antibody test is positive → Patient had a cleared infection

Risk of Vertical Transmission

The risk of vertical transmission to the baby is extremely low in this scenario:

• Vertical transmission is primarily associated with detectable HCV RNA during pregnancy 1
• A meta-analysis of 15 studies with 473 children born to HCV antibody-positive but RNA-negative women found only 1 case of vertical transmission (0.2%) 1
• While rare cases of transmission from RNA-negative mothers have been reported, these may reflect either:
  • Insensitive RNA detection methods
  • Intermittent HCV RNA positivity during pregnancy 1

Management Recommendations

Additional Testing

• No need for HCV viral load monitoring during pregnancy since RNA is negative
• Consider screening for other sexually transmitted infections due to overlapping risk factors:
  • HIV, syphilis, gonorrhea, chlamydia, and hepatitis B 1
  • Screen for hepatitis A immunity 1

Vaccinations

• If patient is not immune to hepatitis A or B, vaccination is recommended during pregnancy 1
• This is safe during pregnancy and helps prevent additional liver damage if exposed to these viruses 1

Labor and Delivery

• No special precautions needed during labor and delivery
• Standard obstetric care is appropriate 2
• No need to avoid:
  • Vaginal delivery
  • Breastfeeding 2

Follow-up

• No hepatology referral is necessary for RNA-negative patients
• No treatment is needed as there is no active infection
• Counsel patient about:
  • Avoiding alcohol during pregnancy 2
  • Risk factors for HCV reinfection (injection drug use, intranasal drug use)
  • The importance of periodic testing if risk factors persist 2

Common Pitfalls to Avoid

1. Misinterpreting antibody positivity as active infection: Always confirm HCV status with RNA testing 1

2. Unnecessary anxiety: Reassure the patient that without detectable virus (RNA negative), there is virtually no risk of transmission to the baby 1

3. Unnecessary interventions: Avoid recommending cesarean delivery or discouraging breastfeeding based solely on HCV antibody status 2

4. Missing other infections: Don't forget to screen for other sexually transmitted infections due to overlapping risk factors 1

5. Repeat testing confusion: If the patient had recent exposure (within 6 months), consider repeat RNA testing as antibodies may take time to develop 1