A pivotal study, led by Michael Boeckh at the Fred Hutchinson Cancer Research Center, has determined that occult infections contribute to 57% of all cases of “idiopathic” pneumonia syndrome (IPS), a condition previously assumed to be non-infectious. HHV-6 was the dominant pathogen representing 29% of cases.
Pathogenic role for HHV-6B in in mesial temporal lobe epilepsy
Japanese investigators published findings suggesting that HHV-6B plays a pathogenic role in epilepsy by enhancing gene expression that induces neuroinflammation and sclerosis in the temporal lobe. HHV-6 DNA levels were significantly higher in the resected tissue of epilepsy patients with sclerosis compared to those without it.
Specific chemokine polymorphism may protect against HHV-6 reactivation and aGVHD in HSCT
A genetic polymorphism of the chemokine CXCL12 was found to be associated with a lower incidence of acute GVHD. Furthermore patients with this polymorphism or receiving cells with the polymorphism were less prone to early HHV-6 reactivation.
ciHHV-6 found in adrenocortical tumors
Since the discovery of chromosomally integrated HHV-6 (ciHHV-6), investigators have wondered about the potential consequences of having chromosome integrated HHV-6 in the genome.
Joshua Hill awarded a 5-year grant to study HHV-6
Congratulations to Joshua Hill, MD, Acting Instructor at the University of Washington and Research Associate at the Fred Hutchinson Cancer Research Center, who has won a K23 grant from the National Institute of Allergy and Infectious Diseases to study HHV-6 in lower respiratory tract disease and chromosomally integrated HHV-6 after stem cell transplantation (SCT).
Elevated levels of HHV-6 DNA in Alzheimer’s, linked to variants in antiviral genes
A group from Italy’s University of Bologna report that genetic defects in antimicrobial defense mechanisms can leave some individuals vulnerable to sub-clinical infections that lead to cognitive decline as they age. They found variations in specific antiviral genes that correlate with HHV-6 DNA levels in brain tissue and blood from patients with Alzheimer’s disease.
Poor Outcome in ICU Patients with HHV-6 & CMV
Intensive care (ICU) patients with co-infections of HHV-6 and CMV are 7.5x more likely to die or have an extended stay in the hospital. On the other hand, single infections with either HHV-6 or CMV did not significantly impact outcome.
Interview with Tetsushi Yoshikawa: Treating HHV-6B seizures
Tetsushi Yoshikawa and Yoshiki Kawamura just published an important study linking HHV-6B in brain tissues to sclerosis in mesial temporal lobe epilepsy. We asked him about this future plans and whether he plans to treat these patients.
Comprehensive new ASM review on HHV-6 (Free Download)
A comprehensive review of HHV-6 has been published in the American Society for Microbiology’s Clinical Microbiology Reviews.
Multiplex PCR; HHV-6 loads higher with steroids
A large-scale multiplex PCR assay developed by a team in Japan was used to study 13 DNA viruses in 105 allogenic hematopoietic stem cell transplant patients. Their findings identify HHV-6 as the most common virus (found in 60% of all patients), and also as the only virus tied to the onset of acute GVHD (p=0.016). Interestingly, HHV-6 reactivation was associated …
Epstein-Barr Virus and Human herpes virus 6 Type A DNA Enhance IL-17 Production in Mice
Since both HHV-6 and EBV have been associated with an increased risk of autoimmune disease development, a group at the American University of Beirut studied whether viral DNA might be capable of triggering IL-17, a cytokine associated with autoimmune disease. They injected BALB/c mice intraperitoneally with either EBV or HHV-6A DNA. They found that both IL-17 and IL-23 were markedly elevated.
Pediatric drug hypersensitivity cases with HHV-6 reactivation have a more severe disease and longer hospital stays
A group at the University of Pennsylvania performed a retroactive study of 29 pediatric patients hospitalized with drug hypersensitivity reactions and found that those who reactivated with HHV-6 had longer lengths of stay (11.5 days vs. 5. days) and more severe illness. They were not able to determine the impact of steroid administration in HHV-6 positive patients.
Heart failure worsens in patients with persistent HHV-6B positive biopsies
Numerous case reports and studies have now tied HHV-6 to myocarditis and cardiomyopathies. To further investigate this relationship, investigators from one of the top cardiology clinics in Europe performed a study to determine the outcome of patients discovered to have HHV-6 in their cardiac tissue during the initial biopsy screen.
ApoE4+ epilepsy patients have higher HHV-6B viral loads and more seizures
A team of Chinese investigators led by Dr. Jin-Mei Li at West China Hospital has identified a possible synergy between a polymorphism of Apolipoprotein E (ApoE) and HHV-6B infection, resulting in a higher viral load and seizure frequency in these patients.
High HHV-6B viral loads found in a subset of epilepsy brain resections
Investigators at the University of Bonn Medical Center in Germany have screened 346 fresh-frozen brain tissue resections from temporal lobe epilepsy (TLE) patients for all nine herpesviruses as well as for RNA viruses including Paramyxovirinae, Phleboviruses, Enteroviruses, and Flavivirus, using qPCR. HHV-6B was the only virus identified.