Here are some of the key findings on the role of HHV-6 in GVHD:
- Aoki and colleagues studied 236 patients who underwent allo-SCT and found that HHV-6 reactivation was associated with a higher incidence of of GVHD (HR =1.87) had significantly higher non-relapse mortality (27.7% versus 13.7%), as well as worse overall survival (42.1% versus 59.0%) compared to those who did not develop HHV-6 reactivation (Aoki 2015).
- A recent study of 106 children who underwent SCT found that progression to grades II-IV GVHD was associated with HHV-6 reactivation in 9/10 (90%). Furthermore, HHV-6 was the only infection that demonstrated this association (Verhoeven 2015).
- In a study that analyzed 13 DNA viruses in 105 allo-SCT patients, HHV-6 was the only virus tied to the onset of aGVHD. The study also revealed that patients treated with steroids were at a significantly greater risk of developing HHV-6 reactivation, and that deactivation was associated with a more severe skin but not liver or gut aGVHD (Inazawa 2015).
- A study 235 allogeneic stem cell transplant patients found HHV-6 reactivation to be strongly associated with delayed platelet engraftment, early post-transplantation mortality, and the development of aGVHD (Dulery 2012).
- A study of 315 allo-SCT recipients by Zerr and colleagues revealed a significant association between high-level (≥1000 copies/mL plasma) HHV-6 reactivation and grades III–IV aGVHDwith overall survival and non-relapse mortality (Zerr 2012).
- A study of 49 HSCT patients found that patients with a viral load ≥87 copies/mL on day 30 post-HSCT developed grades II–IV aGVHD within 100 days, suggesting that HHV-6 reactivation is a high risk factor for aGVHD (Gotoh 2014).
- In a study of 365 patients undergoing HSCT, HHV-6 reactivation was a predictive factor for acute GVHD (HR 1.66) and GVHD was a predictive factor for HHV-6 reactivation (Pichereau 2012).
- Appleton and colleagues who compared skin and rectal biopsies from 34 allogeneic bone marrow transplant recipients and 23 autologous recipients. In allogeneic recipients who developed severe GVHD, HHV-6 DNA was detected in 92% of skin and/or rectal compared to 55% and 22% of biopsies from allogeneic recipients with moderate and mild GVHD, respectively, suggesting an association between HHV-6 DNA and GVHD severity (Appleton 1995).
Key Papers: HHV-6 and Graft-versus-Host Disease