Diagnosis of Hepatitis C Virus Infection
Last updated: July 20, 2012
A 48-year-old executive of a construction company is referred to you for further evaluation of a positive hepatitis C virus (HCV) antibody test. The HCV testing was done because routine laboratory studies showed an alanine aminotransferase (ALT) level of 55 IU/L (range 8 to 35 IU/ml). The patient brings a printout of the lab result to his appointment with you and it states “HCV antibody is positive by enzyme immunoassay—confirmation is suggested”. He denies ever injecting drugs or receiving a blood transfusion and he has does not have any tattoos. He does, however, acknowledge some non-injection use of illicit drugs years earlier. He is married with two children. The patient has not been previously tested for HCV infection. His medical history is otherwise unremarkable, except for an appendectomy about 30 years ago. His review of systems is negative and his physical examination is normal.
Which of the following tests would best determine whether the patient has chronic HCV infection?