BACKGROUND: Pathogenesis of human herpesvirus 6 (HHV-6) encephalitis, in particular difference between HHV-6 encephalitis at the time of primary infection and reactivation remains unclear. OBJECTIVES: To elucidate the mechanism of HHV-6 encephalitis at the time of primary infection and reactivation. STUDY DESIGN: Twenty-two HHV-6 encephalitis patients at the time of primary infection, 6 febrile convulsion (FC) patients caused by HHV-6 infection, and 14 FC patients without HHV-6 infection (non HHV-6 FC) were enrolled. Additionally, 7 stem cell transplant recipients with HHV-6 encephalitis and eight adult controls were also enrolled in this study. Cerebrospinal fluid (CSF) HHV-6 DNA copy numbers and biomarkers levels were compared. RESULTS: Low copy number of CSF HHV-6 DNA was detected in 7 of the 22 patients with HHV-6 encephalitis in primary infection, whereas all seven CSF samples collected from post-transplant HHV-6 encephalitis patients contained high viral DNA copy numbers (P<0.001). CSF concentrations of IL-6 (P=0.032), IL-8 (P=0.014), MMP-9 (P=0.004), and TIMP-1 (P=0.002) were significantly higher in patients with HHV-6 encephalitis in primary infection than non-HHV-6 FC. CSF IL-6 (P=0.008), IL-8 (P=0.015), and IL-10 (P=0.019) concentrations were significantly higher in patients with post-transplant HHV-6 encephalitis than adult controls. CONCLUSION: The present study suggests that the characteristics of HHV-6 encephalitis are different between HHV-6 encephalitis at the time of primary infection and reactivation in transplant recipients.
BACKGROUND: Pathogenesis of human herpesvirus 6 (HHV-6) encephalitis, in particular difference between HHV-6 encephalitis at the time of primary infection and reactivation remains unclear. OBJECTIVES: To elucidate the mechanism of HHV-6 encephalitis at the time of primary infection and reactivation. STUDY DESIGN: Twenty-two HHV-6 encephalitispatients at the time of primary infection, 6 febrile convulsion (FC) patients caused by HHV-6 infection, and 14 FC patients without HHV-6 infection (non HHV-6 FC) were enrolled. Additionally, 7 stem cell transplant recipients with HHV-6 encephalitis and eight adult controls were also enrolled in this study. Cerebrospinal fluid (CSF) HHV-6 DNA copy numbers and biomarkers levels were compared. RESULTS: Low copy number of CSF HHV-6 DNA was detected in 7 of the 22 patients with HHV-6 encephalitis in primary infection, whereas all seven CSF samples collected from post-transplant HHV-6 encephalitispatients contained high viral DNA copy numbers (P<0.001). CSF concentrations of IL-6 (P=0.032), IL-8 (P=0.014), MMP-9 (P=0.004), and TIMP-1 (P=0.002) were significantly higher in patients with HHV-6 encephalitis in primary infection than non-HHV-6 FC. CSF IL-6 (P=0.008), IL-8 (P=0.015), and IL-10 (P=0.019) concentrations were significantly higher in patients with post-transplant HHV-6 encephalitis than adult controls. CONCLUSION: The present study suggests that the characteristics of HHV-6 encephalitis are different between HHV-6 encephalitis at the time of primary infection and reactivation in transplant recipients.
Authors: Ulrike Gerdemann; Laura Keukens; Jacqueline M Keirnan; Usha L Katari; Chinh T Q Nguyen; Anne P de Pagter; Carlos A Ramos; Alana Kennedy-Nasser; Stephen M Gottschalk; Helen E Heslop; Malcolm K Brenner; Cliona M Rooney; Ann M Leen Journal: Blood Date: 2012-11-14 Impact factor: 22.113