Prognostic factors in acute encephalopathy with reduced subcortical diffusion

Acute encephalopathy with reduced subcortical diffusion (AED) covers a spectrum including not only typical acute encephalopathy with biphasic seizures and late reduced diffusion (AESD) but also atypical AESD with monophasic clinical course, or more severe subtypes. Aim of this study is to analyze prognostic factors of AED.

We recruited 33 children with AED, that is, widespread diffusion restriction in cortical and subcortical structures. Their clinical courses, laboratory data, MRI, and the efficacy of treatment were analyzed retrospectively.

Of the 33 children, 20 were males and the mean age at diagnosis was 22 months. Eighteen children had good outcome and 15 had poor outcome. Univariate analysis showed loss of consciousness 24 h after the onset, prolonged seizure at the onset, and mechanical ventilation to be weak predictors of poor outcome. Maximal aspartate aminotransferase, alanine aminotransferase, and creatinine kinase levels were significantly higher in the poor outcome group. Multivariate analysis showed loss of consciousness 24 h after the onset and prolonged seizure at the onset to be poor predictors of AED. Treatment with steroids and/or immunoglobulins did not result in better outcome.

Prolonged seizure at the onset and loss of consciousness 24 h after the onset were seen at early stages of severe AED. Using these features, a prospective study of early intervention in AED should be conducted to further analyze the efficacy of its treatment.