Review summarizes experience from Japan and U.S.
HHV-6 and HHV-7 frequently identified in the spinal fluid of patients with suspected encephalitis
Next-generation sequencing proves valuable for identifying CNS infections in the immunocompetent.
A systematic review and meta-analysis confirms an association between HHV-6B reactivation and increased mortality after hematopoietic cell transplant
Randomized trials are warranted to evaluate if treating HHV-6B reactivation improves outcomes.
Large study from China identifies adverse outcomes associated with, and risk factors for, HHV-6 encephalitis in post-HSCT patients
Greatly increased risk of death, acute GVHD, transplant-associated microangiopathy found.
Growing evidence of rare HHV-7 associated encephalitis and seizures in the immunocompetent
The clinical picture is very similar to HHV-6B encephalitis.
BioFire assay identifies HHV-6 as the most frequent cause of meningoencephalitis in infants 4-11 months
All cases found to be iciHHV-6 were assumed to be false positives.
Small study finds relatively high foscarnet concentrations in CSF in HHV-6 encephalitis
CSF foscarnet concentrati.ons were very near IC50 and were followed by sharp reductions in viral load.
Individuals seropositive for herpesviruses may have greater risk of dementia
Large study from UK Biobank finds that people seropositive for all of these four herpesviruses—HSV-1, HHV-6, HHV-7 and VZV—have greatly increased risk of developing dementia.
HHV-6 DNA often found in cerebrospinal fluid in samples tested for meningitis
Those with viral infections showed no difference in white or red blood cell counts or the protein and glucose levels.
HHV-6 encephalitis following CAR-T cell therapy
A growing number of case reports reveal reactivation similar to that seen after hematopoietic stem cell therapy. Could CAR-T cells be a source of lytic HHV-6?
Imunocompromised patients with HHV-6 encephalitis have a ratio of CSF/blood viral load >1, whereas children with encephalitis due to primary infection have ratios of <1
Immunocompetent cases are typically children experiencing primary infection with high viral loads in the blood; cases in the immunocompromised typically involve reactivation in the brain tissue, with lower viral loads in the periphery
HHV-6 accounted for 5% of all herpetic viral encephalitis in immunocompetent Mexican patients
Psychiatric disorders were the most common prodomal symptom (58%) and this was significantly different from patients with non-herpesvirus encephalitis.
HHV-6 reactivation following haploidentical hematopoietic stem-cell transplant found to predict acute graft versus host disease in China
25% of the patients with HHV-6 reactivation developed aGVHD compared to 18% in those without reactivation.
HHV-6 DNA found in spinal fluid of 8% of patients with aseptic meningitis
Multiplex testing for the causative agents of aseptic meningitis in Saudi Arabia identifies possible etiologic role for HHV-6
No HHV-6 DNA found in the spinal fluid of immunocompetent adults evaluated for limbic encephalitis
While HHV-6B is well known to cause limbic encephalitis in transplant patients, it does not appear to play a role in other forms of limbic encephalitis.