Hemorrhagic shock and encephalopathy syndrome (HSES) is characterized by abrupt onset of hyperpyrexia, encephalopathy(seizure and coma), shock, diarrhea, disseminated intravascular coagulation, and renal and hepatic failure. HSES occurs in infants and prognosis is quite poor; early death in 35-82%, severe neurological squeal in 20-30%, and normal in only 10-20%. The underlying pathogenesis is still unknown. Although previous reports revealed that lowered plasma alpha1-antitrypsin level or elevated cytokine levels including IL-6 and TNF-alpha, the results are controversial.