Impact of human herpesvirus‐6 on the frequency and severity of recurrent hepatitis C virus hepatitis in liver transplant recipients

Abstract

A role of tumor necrosis factor‐alpha (TNF‐α) In the immunopathogenesis of hepatitis C virus (HCV) infection has been proposed. The novel herpes virus, human herpes virus‐6 (HHV‐6), is amongst the most potent inducers of cytokines, including TNF‐α. The impact of HHV‐6 viremia on the progression of recurrent HCV hepatitis was assessed in 51 HCV‐positive liver transplant recipients. The frequency of recurrent HCV hepatitis did not differ between patients with HCV viremia (47.6%, 10/21) as compared with those without HCV viremia (46.7%, 14/30, p=0.9). However, the patients with HHV‐6 viremia had a significantly higher fibrosis score upon HCV recurrence than those without HHV‐6 viremia (mean 1.5 vs. 0.3, p=0.01). An association between cytomegalovirus (CMV) viremia and HCV recurrence was not documented; 50% (15/30) of the patients with CMV viremia and 42.8% (9/21) of those without CMV viremia had recurrent HCV hepatitis (p > 0.5). Receipt of ganciclovir (administered upon the detection of CMV viremia) was associated with lower total Knodell score (mean 5.2 vs. 6.9, p=0.05) and a trend towards lower fibrosis score (mean 0.44 vs. 1.00, p=0.12) in patients with recurrent HCV hepatitis. Thus, HHV‐6 viremia in HCV‐positive liver transplant recipients identified a subgroup of patients at increased risk for early fibrosis upon HCV recurrence.