Fig. 1: The preceding hyponatremia is a useful hallmark for the diagnosis of HHV-6 encephalitis after allogeneic hematopoietic stem cell transplantation.

a Cumulative incidence of HHV-6 encephalitis until 50 days after allo-HSCT. b Cumulative incidence of hyponatremia until 50 days after allo-HSCT. c The serial changes of serum sodium levels a week before the onset of HHV-6 in each patient with hyponatremia. d Diagnostic accuracy index of hyponatremia, CNS dysfunction, and the coexistence of hyponatremia and CNS dysfunction for HHV-6 encephalitis. 95% confidence intervals is shown in parentheses.