Background and purpose: This study was mainly aimed at the comparative analysis of serum S-100B protein in patients with herpes simplex encephalitis (HSE) and tick-borne encephalitis (TBE). S-100B protein is an established biochemical marker of astroglial damage in central nervous system (CNS) injury.
Methods: Serum levels of S-100B were measured using a commercial immunolumino-metric assay (LIA).
Results: Patients with HSE (n = 17) had significantly higher levels of S-100B with median 0.351 microg/l (range 0.017-0.636) compared to patients with TBE (n = 15), who had 0.04 microg/l (range 0.001-0.542) (p < 0.001), as well as controls (n = 17) 0.054 (range 0.004-0.214) (p < 0.001). 11/17 patients with HSE had serum S-100B levels above 0.2 microg/l, in contrast to 1/15 patients with TBE and 1/17 of the control patients. The patients with HSE with serum levels below 0.2 microg/l had a mean 3.2 days disease duration, while patients with levels above 0.2 microg/l had 6 days disease duration.
Conclusions: The serum levels of S-100B in the acute stage of disease were significantly higher in patients with HSE than in patients with TBE or controls. A role for the use of serum S-100B in monitoring CNS damage during initial stage of disease in HSE is suggested.