[Treatment of influenza-associated encephalopathy].

Recently, the number of reports of encephalopathy associated with influenza has increased in Japan. The abrupt onset of seizure and coma after development of high-grade fever is a prominent indicator of CNS involvement. Approximately 600 patients have been reported during 1999-2002. 78% of them are younger than 6 yr old, and the mortality was 30% in 1999 and 2000 seasons. The pathogenicity of brain dysfunction is still unknown. However, elevation of cytokines(TNF-alpha and IL-6) and the damage of vascular endothelial cells were demonstrated. Thus, the prognosis of this illness was extremely poor. Intensive care trial in combination with (1) anti-virals, (2) high dose gamma-grobulin, (3) steroid pulse therapy. (4) high dose AT III, (5) head cooling and (6) plasma exchange has started since 2001, that could reduce the mortality from 30 to 15% in 2001 and 02. In order to establish more effective treatment, further investigation will be necessary.