Clinical application of hepatitis C virus genotyping and quantitation.

Genotyping and quantitation of hepatitis C virus have provided great insights into the pathogenesis of chronic hepatitis C. The assays that are currently available for characterizing HCV remain powerful research tools that will be invaluable in future studies of the next generation of antiviral agents for the treatment of hepatitis C in much the same way that they have provided information about the effectiveness of interferon. Retrospective studies have demonstrated that HCV genotype and viral burden may play some role in disease progression and response to therapy. However, their utility in daily clinical practice in making decisions about treatment regimens or monitoring therapy in an individual patient remains difficult to define. As newer, more effective treatment strategies evolve (longer duration of treatment, combination therapy), previously identified predictors of disease severity or response to treatment may no longer be applicable.