Serum S-100 and neuron-specific enolase for prediction of regaining consciousness after global cerebral ischemia

Background and Purpose-The aim of our study was to assess the use of S-100 protein (S-100) and neuron-specific enolase (NSE) in serum and cerebrospinal fluid (CSF) for the prediction of patients' regaining consciousness after acute global cerebral ischemia. Methods-Sixty-four unconscious patients were followed until the return of consciousness or until death/vegetative state. Serum and CSF samples for measurement of S-100 and NSE using an immunoradiometric assay technique were obtained 24 hours (serum) and 48 hours (CSF) after the acute event and correlated with patient outcome. Results-Values for serum S-100 protein, serum NSE, CSF S-100, and CSF NSE were significantly different in the 2 outcome groups. A serum S-100 value of >0.7 mu g/L was found to be a predictor of not regaining consciousness, with a high positive predictive value (95%) and high specificity (96%). Conclusions-S-100 protein used as serum marker 24 hours after acute global cerebral ischemia gives reliable and independent information on the outcome of the patient that is comparable or superior to that obtained with CSF markers. Therefore, 5-100 may be a serum marker of brain cell damage useful for clinical assessment of these patients.