Monitoring human herpesvirus-6 in patients with autologous stem cell transplantation.

Background/Aim: Due to the increasing number of immunocompromised patients and widely used autologous stem cell transplantation procedures, clinicians have to face with the emergence of infectious diseases. In this setting, we mainly focus our interest on cytomegalovirus (CMV) testing and only in some cases on other herpesviruses (HHV). Herein, we present monitoring of HHV-6 virus re-activation and infection in patients after autologous stem cell transplantation. Materials and methods: One hundred and twenty-one blood and 2 cerebrospinal fluid specimens from 35 patients were tested for the presence of HHV-6 DNA. Results: In 4 patients, a positive HHV-6 signal was detected. In 1 patient, simultaneous detection of CMV and HHV-6 could be observed; however, a low copy number result during CMV testing was obtained. Delayed engraftment or other clinical signs of infection could not be detected in patients with a positive HHV-6 result, except in the case of patient 4 who had limbic encephalitis due to HHV-6 reactivation. Conclusion: Because of the possible severe manifestations of HHV-6 infection in immunocompromised patients, screening of HHV-6 infection or reactivation is recommended as part of the routine laboratory procedure.