Manifestation of adult patients with influenza–associated encephalopathy

Abstract

A detailed survey to investigate the prevalence, clinical features, associated outcomes, and prognostic factors in adult patients with influenza–associated acute encephalopathy was performed. The estimated annual incidence of adult IAE was 0.98/1,000,000 population in Japan. Baseline patient characteristics were 50% male, median age at onset of 54.5 years, and median hospital stay of 15 days. As initial symptoms, 93% of patients showed disturbance of consciousness. Convulsions and delirious behavior were shown in 26% and 40% of patients, respectively. 65% of patients received pulse corticosteroid therapy with methylprednisolone and 21% of patients received intravenous gamma–globulin therapy. Additionally, 21% of patients required mechanical ventilation. 63% of patients achieved a good recovery, but 7% died. Plasma glucose level was significantly associated with poor outcome. Hyperglycemia might be an independent predictor of poor prognosis in IAE patients and reflect systemic hypercytokinemia in IAE pathogenesis.