A third of patients with acute liver failure were found to have a betaherpesvirus infection when tested for all herpesviruses. HHV-6 was the most common infection, followed by CMV and HHV-7. No other herpesviruses were found.
Stanford investigators found that high levels of HHV-6 viremia following allogeneic stem cell transplants were associated end organ disease and greater non-relapse mortality.
HHV-6 is rarely identified as the cause of liver dysfunction in immunocompetent children, in part because HHV-6 is not included in routine testing, and HHV-6 infections can be highly localized to the liver. In this case, an alert team in Arizona identified HHV-6 by needle biopsy.
Two reviews have been published on the roles of HHV-6 in liver transplantation and in pediatric inflammatory cardiomyopathy in the immunocompetent. Both reviews stress the importance of biopsies for diagnosis since HHV-6 DNA is rarely found in the plasma in spite of persistent reactivation in the organ.
HHV-6 infections in the liver transplant patients can’t be diagnosed in the blood. Ganciclovir prophylaxis for CMV cuts the rate of HHV-6 reactivation from 39% to 11%.
A group from Washington University used a bioinformatics system called VirusScan to analyze RNA-Seq data sets from 6,813 human tumors compared to those of adjacent normal tissue. Tumor samples representing 23 different forms of cancer were analyzed. HHV-6, EBV and CMV were found at significantly high levels in GI tract cancer tissue.
Another case of drug induced liver injury accompanied by HHV-6 reactivation has been reported in Japan, the second such case without exanthema to be described. An earlier case was reported last year (Fujita 2015). The authors suggest that drug-induced liver injury cases be investigated for HHV-6 reactivation when liver dysfunction begins several weeks after the initiation of a new drug typically associated with hypersensitivity syndromes.
A group from University of Chicago Medicine urged physicians to consider testing for HHV-6 in cases of unexplained liver failure in immunocompetent patients, especially those with skin rash and upper respiratory symptoms, citing evidence from past studies as well as their own recent case experience.
New article describes acute HHV-6B hepatitis in an HCT recipient and reviews the current literature
French study suggests HHV-6 is a pathological cause of confluent necrosis.
Researchers from the University of Hannover have found a significant association between HHV-6 and decreased graft survival in liver transplant patients.