HHV-6 reactivation tied to increased mortality and acute GVHD in HSCT

In All, Transplant Complications by hhv6foundation

Investigators from the University of Washington, Seattle Children’s Research Institute and Fred Hutchinson Cancer Research Center found high HHV-6 levels (>1,000 DNA copies/mL) associated with both increased mortality and acute graft-versus-host disease (GVHD) grades II-IV (p<0.001). High-level HHV-6 with acute GVHD grades II-IV activation and stages 3-4 skin acute GVHD (p=0.04) were associated with HHV-6 reactivation, and an even stronger association was reported with high-level HHV-6 reactivation (p=0.03). All HHV-6 infections were type B.

The authors also report an association between HHV-6 reactivation and subsequent cytomegalovirus (CMV) reactivation; high-level HHV-6 reactivation was found to be associated with an increased risk of subsequent high-level CMV reactivation (p=0.002).

Finally, the authors also found that high-level HHV-6 reactivation was significantly associated with non-relapse mortality (p=0.02). Of the 40 patients who died from non-relapse mortality 17 (43%) had a fatal infection.

Of 315 post-HSCT patients prospectively studied, 111 (35%) were found to have HHV-6 plasma viremia.

For more information on the dangers of HHV-6 reactivation in transplantation, visit our webpage on HHV-6 & Transplant Complications.