Human herpes virus 6 (HHV-6) infection generally occurs in infancy,and the virus is mostly latent in monocytes and macrophages in the peripheral blood.HHV-6 is reactivated when the immune function is suppressed.HHV-6 DNA can be detected in peripheral blood mononuclear cells in more than 80% of healthy adults in China,while the incidence is low in the adults with normal immune functions.This paper reports a case of multiple organ dysfunction syndrome caused by HHV-6B infection in an adult with normal immune functions.High-throughput sequencing revealed the presence of HHV-6B with high confidence in blood and cerebrospinal fluid.
Adult ; Humans ; Herpesvirus 6, Human ; Multiple Organ Failure/etiology* ; Roseolovirus Infections/complications*

OBJECTIVETo study the potential relationship between HHV-6 activation and acute graft-versus-host disease (aGVHD) after allogeneic hematopoietic cell transplantation (HSCT).

METHODSPeripheral blood samples were collected before and weekly after HSCT from 72 consecutive recipients. HHV-6 DNAemia was monitored by nested polymerase chain reaction (PCR). The genotypes of HHV-6 were identified by Hind III restriction assay.

RESULTSOf the 72 patients, HHV-6 DNAemia were detected in 45 (62.5%) on a median of day 14 (range, 7 - 63 days) after HSCT. Grade I - IV aGHVD occurred in 40 (55.6%) on a median of day 26 (range, 9 -73 days). The median onset time of HHV-6 DNAemia was significantly earlier than that of aGHVD (P = 0.018). Compared with that in HHV-6 DNAemia negative [HHV-6(-)] patients, the cumulative incidence of grade I - IV aGHVD was higher (68.9% vs. 33.3% , P = 0.003) in HHV-6 (+) patients. Cumulative incidence of grade II - IV aGVHD in HHV-6 (+) cohort was also higher than that in HHV-6 (-) cohort (35.6% vs 14.8% , P = 0.027). Cumulative incidence of grade I - IV aGVHD was higher in patients with both HHV-6 and CMV positive (CMV+/HHV-6+) than in those with either CMV (CMV+/HHV-6-) or HHV-6 positive (CMV+/HHV-6+) and neither of them positive (CMV-/HHV-6-) [78.9% (30/38), 55. 6% (5/9) , 14. 3% (1/7) and 22. 2% (4/18), respectively, P = 0. 0001]. Cumulative incidence of grade II - IV aGVHD in CMV+/HHV-6+ group was also higher than that in CMV+/HHV-6-, CMV-/HHV-6+ and CMV-/HHV-6- groups [42.1% (16/38), 22.2% (2/9), 0% (0/7) and 11.1% (2/18), P = 0. 008].

CONCLUSIONSPatients with HHV-6 activation or HHV-6/CMV co-infection maybe involved in the occurrence of aGVHD after HSCT.

Cytomegalovirus ; genetics ; isolation & purification ; Genes, Viral ; Graft vs Host Disease ; etiology ; virology ; Hematopoietic Stem Cell Transplantation ; adverse effects ; Herpesvirus 6, Human ; genetics ; physiology ; Humans ; Polymerase Chain Reaction ; methods ; Postoperative Complications ; etiology ; virology ; Roseolovirus Infections ; etiology

In order to study the prevalence of human herpesvirus 6 (HHV-6) in allogeneic hematopoietic stem cell transplant (allo-HSCT) recipients in China and to analyze the relationship between HHV-6 and cytomegalovirus (CMV) infection in post-HSCT patients, nested polymerase chain reaction (PCR) was used to monitor HHV-6 DNAemia in 72 consecutive allo-HSCT recipients. 680 EDTA anticoagulated peripheral blood specimens were gathered before HSCT or weekly until 12 weeks after allo-HSCT. The variants of HHV-6 were identified by Hind III restriction analysis. CMV-pp65 antigenemia was detected by immunofluorescence stain. The results showed that HHV-6 DNAemia was detected at least once in 62.5% (45/72) of the patients on the median day 14 (range, 7 - 63 days) after allo-HSCT, and HHV-6B was the predominant variant. CMV antigenemia was detected at least once in 65.3% (47/72) of the patients on the median day 43 (range, 14 - 105 days) after allo-HSCT. Co-infection of HHV-6 and CMV (HHV-6+/CMV+) occurred in 52.8% (38/72) recipients. The onset of HHV-6 DNAemia was earlier than that of CMV antigenemia (P < 0.0001). Patients with HHV-6 DNAemia positive were more likely to have concurrent CMV antigenemia than HHV-6 DNAemia negative patients (84.4% vs 33.3%, P = 0.0001) after allo-HSCT. Among the herpesvirus related disease, the relatively high incidence of hemorrhage cystitis (HC) occurred in 23.6% (17/72) of post-HSCT patients. 88.2% (15/17) of HC developed in HHV-6 positive patients, and 82.3% (14/17) occurred in CMV+/HHV-6+ patients. It is concluded that infection of HHV-6, co-infection of HHV-6 and CMV, commonly occurred in post-HSCT patients in China, HHV-6 infection closely related to CMV antigenemia.
Adolescent ; Adult ; Child ; China ; epidemiology ; Cytomegalovirus ; genetics ; isolation & purification ; Cytomegalovirus Infections ; complications ; epidemiology ; DNA, Viral ; blood ; genetics ; Female ; Hematopoietic Stem Cell Transplantation ; adverse effects ; Herpesvirus 6, Human ; isolation & purification ; physiology ; Humans ; Male ; Middle Aged ; Polymerase Chain Reaction ; Prevalence ; Roseolovirus Infections ; complications ; epidemiology ; virology