High incidence of human herpesvirus 6 infection with a high viral load in cord blood stem cell transplant recipients

• DOI: 10.1182/blood.v100.6.2005
• Publication Date: 2019-10-14T04:48:09Z
• Authors: Junji Sashihara; Keiko Tanaka-Taya; Shinya Tanaka; Kiyoko Amo; Hiromi Miyagawa; Gaku Hosoi; Tomokuni Taniguchi; Takafumi Fukui; Naoki Kasuga; Toshiya Aono; Masahiro Sako; Junichi Hara; Koichi Yamanishi; Shintaro Okada
• Keywords: Adult; 0301 basic medicine; Transplantation Conditioning; Adolescent; Herpesvirus 6, Human; Incidence; Hematopoietic Stem Cell Transplantation; Infant; Roseolovirus Infections; Viral Load; Fetal Blood; Polymerase Chain Reaction; 3. Good health; Survival Rate; 03 medical and health sciences; Child, Preschool; DNA, Viral; Humans; Transplantation, Homologous; Virus Activation; Child

AbstractHuman herpesvirus 6 (HHV-6) infection in recipients of cord blood stem cell transplants (CBSCTs) was estimated by semiquantitative and real-time quantitative polymerase chain reaction (PCR) and reverse-transcription PCR. Of the CBSCT recipients, 7 (70%) of 10 had active HHV-6 infection after transplantation, and all 7 were inferred from their age to have already had a primary infection. Because HHV-6 DNA is seldom detected in cord blood, these cases were considered likely to represent reactivation. In contrast, the 3 patients without HHV-6 infection were all believed to be naive regarding HHV-6 primary infection because of their age and the results of PCR assays given before the transplantation procedure. The incidence of HHV-6 infection after transplantation was significantly higher (P < .05) than after bone marrow (BM) transplantation and peripheral blood stem cell (PBSC) transplantation, when recipients without primary HHV-6 infection prior to transplantation were excluded (CBSCT, 100%; BMT/PBSCT, 56.3%). Real-time PCR revealed a higher level of viral DNA in the peripheral blood mononuclear cells from CBSCT recipients than from BMT/PBSCT recipients or patients with exanthem subitum (P < .05). HHV-6 mRNA of the U79/80gene was also detected by reverse-transcription PCR in all analyzed patients with HHV-6 infection. Its detection was correlated with the emergence of viral DNA in the plasma and symptoms such as fever and rash. Thus, HHV-6 infection was more frequent and the viral load was higher in CBSCT recipients with prior primary infection.