Cerebrospinal fluid levels of soluble tumour necrosis factor receptor in acute encephalitis

Soluble tumour necrosis factor receptor (sTNF-R) inhibits the action of TNF-alpha. The level of sTNF-R reflects the true biological activity of TNF-alpha. We investigated whether sTNF-R in cerebrospinal fluid (CSF) and serum increases during the acute stage in patients with acute encephalitis by measuring p60 sTNF-R using a sandwich enzyme immunoassay. The levels of sTNF-R were significantly higher in the CSF and serum of children with acute encephalitis than in those of control subjects. The patients with acute encephalitis who died or had severe neurological sequelae had higher CSF sTNF-R levels than those who survived. There were no significant differences in the serum sTNF-R, serum C-reactive protein and CSF protein levels, and CSF cell counts between the two groups. The sTNF-R levels of 4.0 ng/ml or higher identified patients with acute encephalitis who had neurological sequelae with a sensitivity of 100% (8/8), a specificity of 100% (8/8), and a predictive value of 100% (8/8). The 95% confidence interval for these three values is 63-100%. Our findings suggest that the CSF level of sTNF-R during the acute stage of encephalitis is important for predicting neurological sequelae.