title: HHV-6 encephalitis in umbilical cord blood transplantation: a systematic review and meta-analysis.
abstract: Reactivation of human herpesvirus-6 (HHV-6) frequently occurs following hematopoietic SCT (HSCT), and has been associated with clinical consequences in many patient populations. HHV-6 reactivation and HHV-6 encephalitis seem to occur more frequently in patients undergoing HSCT with cord blood (CB) as the stem cell source. We have conducted a systematic literature review and meta-analysis to investigate the clinical significance of this correlation. A systematic review of publications indexed in PubMed was performed for HSCT studies published over the past 10 years that fit inclusion criteria. Data on prevalences of HHV-6 reactivation and HHV-6 encephalitis post HSCT were abstracted from 19 papers. Meta-analyses were conducted to calculate combined prevalence estimates. The prevalences of HHV-6 reactivation and encephalitis were compared among CB vs non-CB HSCT. Prevalences of HHV-6 reactivation and HHV-6 encephalitis were significantly higher in patients receiving CB as the stem cell source than in patients receiving another stem cell source (72.0% vs 37.4%, P<0.0001; 8.3% vs 0.50%, P<0.0001, respectively). HHV-6 reactivation and HHV-6 encephalitis are significant complications in the post-HSCT setting, particularly in patients receiving CB as the stem cell source. Thus, patients undergoing umbilical CB transplantation should be closely monitored for HHV-6 reactivation.
authors.affiliation: Department of Pediatrics, Section of Hematology-Oncology, Baylor College of Medicine, Houston, TX 77030, USA. scheurer@bcm.edu
authors.forename: M E
authors.initials: ME
authors.lastname: Scheurer
authors.forename: J C
authors.initials: JC
authors.lastname: Pritchett
authors.forename: E S
authors.initials: ES
authors.lastname: Amirian
authors.forename: N R
authors.initials: NR
authors.lastname: Zemke
authors.forename: P
authors.initials: P
authors.lastname: Lusso
authors.forename: P
authors.initials: P
authors.lastname: Ljungman
mesh_terms: D036101:Cord Blood Stem Cell Transplantation; D018792:Encephalitis, Viral / Q000209:etiology / Q000378:metabolism / Q000517:prevention & control; D005260:Female; D015654:Herpesvirus 6, Human; D006801:Humans; D008297:Male; D015995:Prevalence; D019349:Roseolovirus Infections / Q000209:etiology / Q000401:mortality / Q000517:prevention & control; D014184:Transplantation, Homologous