Evaluating the prognosis and degree of brain injury by combined S-100 protein and neuron specific enolase determination

Xihua Wang; Xinding Zhang

摘要：Background:S-100 and neuron specific enolase(NSE)possess the characteristics of specific distribution in brain and relative stable content.Some studies suggest that combined detection of the both is of very importance for evaluating the degree of brain injury.OBJECTIVE: To observe the changes of S-100 protein and NSE levels at different time points after acute brain injury,and evaluate the values of combined detection detection of the both for different injury degrees,pathological changes and prognosis.DESIGN: Case-control observation SETTING: Department of Neurosurgery,Second Affiliated Hospital,Lanzhou University.PARTICIPANTS:Thirty-four inpatients with brain injury,19 males and 15 females,aged 15 to 73 years.who received treatment between September 2005 and May 2006 in the Department of Neurosurgery. Second Affiliated Hospital,Lanzhou University,were recruited.The patients were admitted to hospital at 24 hours after brain injury.After admission,skull CT confirmed that they suffered from brain injury.Following Glasgow coma score(GCS)on admission,the patients were assigned into 3 groups:severe group(GCS 3 to 8 points,n=15).moderate group(GCS 9 to 12 points,n=8)and mild group(GCS 13 to 15 points,n=11).Following Glasgow outcome scale(GOS)at 3 months after brain injury,the patients were assigned into good outcome group (GOS 4 to 5 points,good recovery and moderate disability included,n=19)and poor outcome group(GOS 1 to 3 points,severe disability,vegetative state and death,n=15).Ten subjects who received health examination concurrently were chosen as normal control group,including 6 males and 4 females,aged(45.4±14.3)years.In our laboratory,the normal level of NSE was≤15.2 ng/L,and that of S100 was≤0.105 μg/L.METHODS:①Blood samples of control group were collected when the subjects received health examination Blood samples of patients with brain injury were collected at 24 hours,3,7 and 14 days after injury.According to the instructions of NSE and S-100 kits purchased from Roche Company,serum NSE and S-100 levels were determined by electrochemiluminescence immunoassay(ECLIA). ②Analysis of variance was used for intergroup companson,Spearman correlative analysis for comparison of different GCS and GOS.and linear regression analysis for comparison of correlation of two factors.MAIN OUTCOME MEASURES:①The dynamic changes of NSE and S-100 of patients with different brain injuries and their correlations with GCS.②The dynamic changes of NSE and S-100 of patients with different outcomes and their correlations with GOS.RESULTS:Thirty-four patients with brain injury and ten healthy persons were involved in the result analysis.①Overall change rule of NSE and S100 after brain injury:NSE of patients with brain injury reached its peak at 24 hours after injury,then was gradually decreased with time and was below normal level in the 2nd week.The overall tendency of S-100 was the same as that of NSE in patients with brain injury.②The dynamic changes of NSE and S-100 of patients with different brain injuries and their correlations with GCS:NSE and S-100 levels at 24 hours after injury were significantly negatively correlated with those on admission(r=-0.537,-0.731,P＜0.05).At 24 hours after injury,serum NSE and S-100 levels of patients with mild.moderate and severe brain injuries were significantly higher than those of control group(P＜0.05):At 14 days after brain injury serum NSE and S-100 levels of patients with mild and severe brain injury were close to those of control group (P＞0.05):While at 24 hours,3,7 and 14 days after brain injury.the serum NSE and S-100 levels of patients with severe brain injury were significantly higher than those of control group (all P＜0.05).NSE level of patients with mild brain injury was decreased to normal level at 7 days after injury and that of patients with moderate brain injury at 14 days after injury.S-100 level of patients with mild and moderate brain injury was decreased to normal level at 14 days after injury.Serum NSE and S-100 levels of patients with severe brain injury always kept over normal level and those of patients with mild brain injury reached peak value at 3 days after injury.③The dynamic changes of NSE and S-100 levels of patients with different outcomes and their correlations with GOS:serum NSE and S-100 levels at 24 hours after injury were significantly negatively correlated with GOS(r=-0.573,-0.756,P＜0.05).It suggested that the severer the injury was.the lower the GOS was.At 24 hours,3,7 and 14 days after injury,serum NSE and S-100 levels of patients in good outcome group were significantly lower than those of poor outcome group(P＜0.05).CONCLUSION:The injury degree and prognosis of patients with brain injury are correlated with serum NSE and S-100 levels.The detection of serum S-100 and NSE levels after injury can be used for evaluating injury and prognosis of brain injury