Figure 3.

IL-18 is a sensitive indicator of hepatitis C virus (HCV) infection. Plasma IL-18 concentration (•), alanine aminotransferase (ALT [◊]), and HCV RNA (shaded) at the onset of initial HCV infection are shown for 6 representative subjects in which ALT elevation occured later than initial detection of HCV RNA (A). Sensitivity of IL-18 in detecting reinfection events is shown in (B). Subject 57 was reinfected at day 222 (vertical arrow); an increase in plasma IL-18 (•) is shown, whereas no significant change in ALT (◊) at this reinfection is shown.