COMPLICATIONS - INFECTIONS

I. Lautenschlager¹, R. Loginov¹, T. Karlsson¹, K. Höckerstedt^2
1Department Of Virology, Helsinki University Hospital, Helsinki/FINLAND, ²Transplantation And Liver Surgery Clinic, Helsinki University Hospital, Helsinki/FINLAND

Body: Introduction: Human herpesvirus-6 (HHV-6) activation, mostly of HHV-6B, is common after liver transplantation (LT). Most HHV-6 reactivations are asymptomatic, but encephalitis, hepatitis or graft dysfunction have been described. Clinical experience on antiviral therapy is limited, but based on in vitro studies, the antiviral drugs effective against cytomegalovirus (CMV), have also activity against HHV-6. In this study, we investigated the efficiency of antiviral prophylaxis, given to the CMV-seronegative risk patients receiving a liver graft from the seropositive donor, in preventing HHV-6 reactivation. Methods: Of 196 consecutive adult LT patients 32 belonging to the CMV high risk group received antiviral prophylaxis (valganciclovir 900 mg daily and/or i.v. ganciclovir 5mg/kg/d) up to 3 months after transplantation. The patients were frequently monitored for CMV by real-time quantitative PCR and HHV-6 reactivations were demonstrated by the antigenemia test in peripheral blood mononuclear cells (PBMC) using immunoperoxidase staining and monoclonal antibodies against HHV-6B and HHV-6A. Intragraft HHV-6 infections were demonstrated in liver biopsies using the same antibodies and immunostaining. Results: During antiviral prophylaxis, no break-through CMV infections were recorded. On the contrary, HHV-6 antigenemia was detected in 12/32 (37%) patients appearing mean 12 days (range 7-22 days) after transplantation. All reactivations were caused by HHV-6B. In three patients HHV-6 antigens were also detected in the liver biopsy obtained due to graft dysfunction, in two cases associated with acute allograft rejection. Conclusions: HHV-6B reactivations were common during antiviral prophylaxis against CMV after LT. At least in three cases also the transplant was infected. Valganciclovir (ganciclovir) prophylaxis did not prevent HHV-6B infections in adult liver transplant patients.

Disclosure: All authors have declared no conflicts of interest.