What lab test is needed to check if a patient's hepatitis has returned?

Testing for Recurrent Hepatitis C Infection

To determine if a patient's hepatitis C has returned, you should order an HCV RNA test, as this is the only reliable way to detect active HCV infection and recurrence.

Understanding Hepatitis C Testing

Diagnostic Markers

• HCV RNA testing is the gold standard for detecting active hepatitis C infection and is essential for confirming recurrence or reinfection 1
• Anti-HCV antibodies persist after viral clearance (whether spontaneous or treatment-induced) and therefore cannot be used to determine if hepatitis C has returned 1
• HCV core antigen testing can be used as an alternative when HCV RNA testing is not available, though it is less sensitive 1

Testing for Recurrence After Treatment

• HCV reinfection should be suspected when HCV RNA or HCV core antigen reappears after achieving sustained virologic response (SVR) in individuals with risk factors 1
• Assessment for HCV recurrence is only necessary if the patient has ongoing risk for HCV infection or experiences unexplained hepatic dysfunction 1
• A quantitative HCV RNA assay, rather than an anti-HCV serology test, is recommended to test for HCV recurrence or reinfection 1, 2

Interpreting Test Results

Positive HCV RNA Test

• Indicates active HCV infection, which could be:
  • Recurrence of the original infection
  • Reinfection with a new strain 1
• Confirmation of reinfection requires demonstration that the infection is caused by a different genotype or a distantly related strain of the same genotype using sequencing and phylogenetic analysis 1

Negative HCV RNA Test

• Indicates absence of active HCV infection 1, 2
• If clinical suspicion remains high despite a negative result, consider:
  • Repeat testing, as HCV RNA levels can fluctuate 1
  • Intermittent HCV RNA positivity has been observed among persons with chronic HCV infection 1, 2

Special Considerations

Timing of Testing

• For patients with suspected recurrence, a single negative HCV RNA result may not be conclusive 1
• If clinical suspicion is high, repeat testing may be warranted as HCV RNA can be intermittently detectable 1, 2

Common Pitfalls

• Relying solely on anti-HCV antibody testing to detect recurrence (antibodies typically remain positive after clearance) 1, 2
• Failing to recognize that a single negative HCV RNA test may not definitively rule out recurrence if the patient has risk factors or symptoms 1
• Not considering HCV core antigen testing as an alternative when HCV RNA testing is unavailable or unaffordable 1

Follow-up Recommendations

• For patients with confirmed recurrence (positive HCV RNA):
  • Full evaluation for retreatment should be initiated 1
  • Assessment of liver disease severity is recommended 1
• For patients without recurrence (negative HCV RNA):
  • If no advanced fibrosis was present before treatment, no additional follow-up is recommended 1
  • If advanced fibrosis (F3-F4) was present, continue surveillance for hepatocellular carcinoma with twice-yearly abdominal imaging 1