Elevation of neuron-specific enolase in serum and cerebrospinal fluid of early stage Creutzfeldt-Jakob disease

Objective - To investigate the levels of neuron-specific enolase (NSE) in serum and cerebrospinal fluid (CSF) of patients with early stage Creutzfeldt-Jakob disease (CJD). Methods - The levels of NSE in serum and CSF were examined in 6 cases with CJD patients. The levels of NSE in CSF were measured in 8 age matched control patients with other neurological diseases and the levels of serum NSE were also measured in another 8 age matched control patients with other neurological diseases. The groups of 8 age matched control patients consisted of 1 same patient and 7 different patients in the 2 control groups both for serum and CSF. Results - The level of serum NSE in CJD (17.3 ± 7.0 ng/ml, mean ± SD) was significantly higher than that of controls (6.5 ± 1.6) (P < 0.02) as was the case in CSF (79.3 ± 53.3 ng/ml) vs (9.6 ± 2.9) (P < 0.03). Conclusion - Although mean NSE levels of CJD were higher in CSF than in the serum, there still is a case with higher serum NSE level than CSF. These results suggest that the mechanism of elevation of serum NSE may not be a simple leakage from CSF, and that the measurement of serum NSE level may be useful for diagnosis of early stage CJD.