An anti-HCV test remains positive in a 60-year-old woman. Which test is most appropriate for follow-up to determine current or past infection?

• A. Anti-HCV titer
• B. HCV RNA
• C. HCV Genotype
• D. ALT level

Answer: (B)

Antibody tests against HCV show past exposure, not whether the virus is currently present, because antibodies can remain after the infection has cleared. To determine if infection is active, look for the virus itself: HCV RNA. Detectable HCV RNA means there is ongoing viral replication and current infection (acute or chronic). If HCV RNA is not detected, there isn’t an active infection, though antibodies may still be positive from a prior infection. Other options don’t address current viral presence as directly: genotype helps tailor therapy once infection is confirmed, ALT reflects liver injury rather than infection status, and an anti-HCV titer isn’t routinely used to distinguish active from past infection.