Sorted By Test Name - Mayo Medical Laboratories

anti-HCV antibodies detectable in their serum. In general, 70% to 80% of these individuals will develop
chronic infection with ongoing viral replication in the liver and detectable HCV RNA in serum,
eventually causing fibrosis and cirrhosis. The other 20% to 30% of infected individuals recover from the
infection without evidence of viral replication or the presence of detectable HCV RNA. In patients with
chronic HCV infection, the response to combined interferon-alpha and ribavirin therapy is correlated with
pretreatment serum HCV RNA levels (viral load) and HCV genotype. Similarly, the optimal duration of
combined interferon and ribavirin therapy can be determined from the patient's pretreatment viral load and
HCV genotype. Clinical studies also indicate that a decrease in HCV RNA levels of more than 2 log
IU/mL at 4 weeks and/or 12 weeks of therapy is predictive of an increased chance of achieving a
sustained virologic response (undetectable HCV RNA levels in serum 6 months after completing antiviral
therapy). Despite typically undergoing a longer duration of treatment (48 weeks versus 24 weeks),
patients with chronic infection due to HCV genotypes 1 and 4 generally have less favorable sustained
virologic response rates (40%-60%) than those infected with genotypes 2 and 3 (>80%). To determine the
duration of treatment and monitor the response to anti-HCV therapy, HCV RNA levels in serum are
typically measured in patients at 0 (baseline) 4 weeks (rapid virologic response, RVR), 8 weeks, 12 weeks
(early virologic response: EVR), end-of-treatment (24, 28, or 48 weeks depending on HCV genotype and
treatment response), and 24 weeks post-treatment (sustained virologic response: SVR). -The following
algorithms are available in Special Instructions: -Recommended Approach to the Diagnosis of Hepatitis C
-Alternative Approaches to the Diagnosis of Hepatitis C -Chronic Hepatitis C Standard-of-Care Treatment
Algorithm: Combined Pegylated Interferon and Ribavirin Therapy -Chronic Hepatitis C Treatment
Algorithm: HCV Genotype 1 with Telaprevir-containing Combination Therapy -Chronic Hepatitis C
Treatment and Monitoring Algorithm: Boceprevir-Containing Combination Therapy (HCV Genotype 1
only)
Useful For: Detection of acute hepatitis C virus (HCV) infection (ie,