Spontaneous resolution of chronic hepatitis C virus infection after antiviral treatment and relapse

Clearance of acute hepatitis C virus (HCV) infection is associated with strong and multi-specific cellular immune responses which are often weak in chronic hepatitis C. We here report a case of spontaneous and sustained resolution of chronic hepatitis C virus infection in the absence of apparent HCV-specific immunity. The patient received standard antiviral therapy for chronic HCV infection and was HCV-RNA negative at the end of treatment but relapsed between follow-up week 4 and 12. Surprisingly, from follow-up week 28 on, he persistently was HCV-RNA negative in serum, even when being tested with the highly sensitive TMA-assay (cut-off 5-10IU/ml). ALT levels were within the normal range throughout follow-up. Virus-specific CD4+ T cell responses were prospectively analysed during the relapse period and during spontaneous resolution by interferon-gamma ELISPOT assays. Importantly, no HCV-specific cellular immune responses were detectable at any time-point. The patient suffered from an acute respiratory tract infection before HCV clearance and serum IL-8 levels were significantly increased during this period. Thus, spontaneous resolution of hepatitis C after antiviral treatment and relapse may occur even in the absence of hepatitis flares and apparent HCV-specific immune responses in single cases. The role of heterologous infections for HCV clearance requires further investigation.