The latest article in our Clinical Practice series, Chronic Hepatitis C Infection, reviews the evaluation and initial management of chronic hepatitis C infection, with particular attention to the use of new directly acting antiviral agents in treatment regimens.
Infection with HCV affects an estimated 180 million people globally. It is a leading cause of chronic hepatitis, cirrhosis, and liver cancer and a primary indication for liver transplantation in the Western world.
• What are the predominant risk factors for hepatitis C virus infection?
The predominant risk factor for HCV acquisition is injection-drug use; among U.S. adults 20 to 59 years of age with any history of illicit injection-drug use, the prevalence of HCV infection is greater than 45%. Other risk factors include blood transfusion before 1992, high lifetime number of sexual partners, and iatrogenic transmission, including through dialysis; in large series, 15 to 30% of patients report no risk factors.
• Approximately what percentage of patients with chronic hepatitis C virus infection have progression to cirrhosis?
Although the natural history of HCV infection is highly variable, an estimated 15 to 30% of patients in whom chronic infection develops have progression to cirrhosis over the ensuing three decades. A number of factors, including a longer duration of infection, an older age at the time of exposure, male sex, coinfection with other viruses such as HIV, and daily alcohol consumption, but not viral level or genotype, have been consistently associated with an increased risk of fibrosis.
Table 1. Predictors of a Favorable Response to Treatment with Peginterferon and Ribavirin.
Morning Report Questions
Q: What methods can be used to quantify hepatic fibrosis?
A: Several methods have been used to quantify hepatic fibrosis, including the simple aspartate aminotransferase:platelet ratio index and commercially available assays of some or most of the following biomarkers: (alpha)2-macroglobulin, (alpha)2-globulin, (gamma)-globulin, apolipoprotein A-I, (gamma)-glutamyltransferase, total bilirubin, and hyaluronic acid.
Q: What treatment is the standard of care for all HCV genotypes?
A: Over the past decade, on the basis of considerable data from randomized trials, pegylated interferon (peginterferon) plus ribavirin became the standard of care for all HCV genotypes. Regardless of the infecting genotype, the likelihood of a sustained virologic response is lower among patients with a high pretreatment HCV RNA level and higher among patients with better adherence to antiviral therapy.