Correlations of cytokine levels in cerebrospinal fluid and peripheral blood with outcome of HHV-6B encephalitis after hematopoietic stem cell transplantation.

We found that one week before onset of HHV-6B encephalitis, poor prognosis patients had high plasma concentrations of IL-6, IL-7, and MCP-1 and low concentrations of IL-12. At the onset of encephalitis, high concentrations of IL-6 and IL-8 in CSF were more common in the poor prognosis group, consistent with other evidence that IL-6 can have a role in CNS disturbances. Our findings show that specific cytokine status is associated with severe brain damage in patients with HHV-6B encephalitis, demonstrate prognostic value of plasma IL-6 concentrations, and suggest evaluation of anti-cytokine therapeutics in patients with HHV-6B encephalitis.