Rapid detection of hepatitis C virus RNA by a reverse transcription loop-mediated isothermal amplification assay.

The usefulness of reverse transcription loop-mediated isothermal amplification (RT-LAMP) for the rapid diagnosis of hepatitis C virus (HCV) RNA was evaluated. This assay showed higher sensitivities than that of nested RT-PCR, with a detection limit of 600 IU mL(-1) , and no cross-reactivity was observed with hepatitis A virus, hepatitis B virus and hepatitis E virus. Furthermore, 106 stored sera from recently diagnosed cases were retrospectively investigated with real-time RT-PCR, the nested RT-PCR, in parallel with this new assay. The general detection rates of HCV RT-LAMP, real-time PCR and the nested RT-PCR for 106 stored sera samples were 95%, 96% and 88%, respectively. This study provides the first data on the usefulness of HCV RT-LAMP in the diagnosis of HCV RNA, especially in the early clinical diagnosis of acute HCV infection.