Methods: Time courses of the serum concentrations of two brain-specific proteins (BSP), alpha(1) brain globulin (alpha(1)BG, an astroglial marker) and neuron-specific enolase (NSE), were studied in patients with severe tick-born encephalitis (TBE) and Lyme disease (LD; neuroborreliosis). The concentrations were determined on the second day of the acute phase and then on the 7th, 12th, 18th, and 23rd days. Apparent rate constants for the elimination of the BSP from blood (k(e)) were calculated with the non-linear regression.
Results: In patients with TBE, the highest serum concentrations of alpha(1)BG and NSE, observed on the second day, were followed by their monotonic decrease to the normal levels reached by the 23rd day. The mean k(e) values for alpha(1)BG and NSE were found to be significantly different (0.086+/-0.003 vs. 0.057+/-0.006 day(-1), respectively; p<0.05). Higher serum levels of both BSP were observed in the more severe clinical cases and in the cases with unfavorable outcomes. Similar profiles were also observed for the serum alpha(1)BG and NSE in LD.
Conclusions: These results suggest that, in the patients examined, the blood-brain barrier was partially impaired; the quantitative parameters of the serum BSP time courses can be indicative of the extents of the neuronal and/or glial lesions.