Investigators urge careful monitoring for HHV-6 and ciHHV-6.
Could some complications of CAR-T cell therapy be secondary to HHV-6 infection?
Clearly documented cases of HHV-6 encephalitis have been reported, but some are missed because they were classified as ICAN or because HHV-6 testing was not performed in patients with mental status changes.
While unlikely to trigger the cytokine storm, HHV-6 infection may perpetuate it, and contribute directly to cytopenias and pneumonia.
T-cell responses correlate directly with clinical symptoms, and were better predictors of HHV-6 disease than viral load or total CD3+ counts.
The severity of DIHS/DRESS cases was significantly correlated with the frequency of CD134+ cells.
Observational study suggests that an early one-week treatment at the first sign of viral reactivation may achieve clinical benefits and avoid antiviral toxicity.
HHV-6A was the most common virus identified, but was not linked to worse outcomes compared to other viral infections.
CSF foscarnet concentrati.ons were very near IC50 and were followed by sharp reductions in viral load.
Study finds value in HHV-6 testing of other tissues, as well as blood, and of routine testing for iciHHV-6 in both donors and recipients of allo-HCT.
Data from 13,363 transplant patients underline the importance of preventing, diagnosing and treating viral reactivation.
Review highlights the importance of cell mediated immunity and the limitations of antivirals, vaccines and immunoglobulin therapy for HHV-6, VZV and HSV.
These values may help determine the type of treatment transplant patients should receive: antiviral or adoptive T-cell therapy or a reduction in immunosuppression.
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?
A small pediatric study found that adoptive NK cell infusions eliminated HHV-6B encephalitis, while maintaining a low rate of GVHD. At a ratio of NK/CD4 >2, the HHV-6B reactivation rate dropped dramatically.