Strong Correlation between Liver and Serum Levels of Hepatitis C Virus Core Antigen and RNA in Chronically Infected Patients

HCV core antigen (Ag) and HCV RNA levels were evaluated in matched liver biopsy samples and sera from 22 patients with hep-atitis C infection by using the quantitative Architect HCV Ag immunoassay and a real-time RT-qPCR assay, respectively. The data showed a strong correlation between liver and serum compartments of HCV Ag levels (r 0.80) and HCV RNA levels (r 0.87). In summary, the serumHCVAg and RNA levels reflect the intrahepatic values. Hepatitis C virus (HCV) is an important human pathogen;worldwide, over 170 million people are chronically infected. The standard virologic diagnosis of infection is based on the de-tection of specific anti-HCV antibodies and cannot distinguish between past and active infections. Therefore, assays of the HCV RNA load in serum or plasma have become essential for confirm-ing active infections and guiding the initiation and continuation of treatment with pegylated interferon and ribavirin or other an-tivirals. At present, real-time PCR is the benchmark technique for detecting and quantitating HCV RNA in clinical practice, with limits of detection of 10 to 15 IU/ml (4, 7, 15). However, these assays require high levels of technical skill and are labor-intensiv