Differential Effects of Alcohol Intoxication on S100B Levels Following Traumatic Brain Injury

Reliability of serum S100B measurement following mild traumatic brain injury: a comparison of assay measurements from two laboratories

OBJECTIVE

There is enormous research and clinical interest in blood-based biomarkers of mild traumatic brain injury (MTBI) sustained in sports, daily life, or military service. We examined the reliability of a commercially available assay for S100B used on the same samples by two different laboratories separated by 2 years in time.

METHODS AND PROCEDURES

A cohort of 163 adult patients (head CT-scanned, n = 110) with mild head injury were enrolled from the emergency department (ED). All had Glasgow Coma Scale scores of 14 or 15 in the ED (94.4% = 15). The mean time between injury and venous blood sampling was 2.9 h (SD = 1.4; Range = 0.5-6.0 h). Serum S100B was measured at two independent centers using the same high throughput clinical assay (Elecsys S100B®; Roche Diagnostics).

RESULTS

The Spearman correlation between the two assays in the total sample (N = 163) was r = 0.93. A Wilcoxson Signed Ranks test indicated that the median scores for the values differed (Z = 2,082, p < .001, Cohen's d = 0.151, small effect size). The values obtained from the two laboratories were very similar for identifying traumatic intracranial abnormalities (sensitivity = 80.1% versus 85.7%).

CONCLUSIONS

The serum S100B results measured using the same assay in different laboratories yielded highly correlated and clinically similar, but clearly not identical, results.

Elevated Serum Levels of NSE and S-100β Correlate with Increased Risk of Acute Cerebral Infarction in Asian Populations

BACKGROUND

We investigated the clinical value of serum levels of neuron-specific enolase (NSE) and human soluble protein-100β (S-100β) in acute cerebral infarction (ACI) patients.

MATERIAL AND METHODS

A literature search of electronic databases identified relevant case-control studies that examined the correlations between NSE and S-100β serum levels, and ACI. The retrieved studies were screened based on our strict inclusion and exclusion criteria, and high-quality studies were subsequently selected for meta-analysis. STATA software (Version 12.0, Stata Corporation, College Station, TX, USA) was utilized for statistical analysis.

RESULTS

A total of 13 case-control studies, containing 911 ACI patients and 686 healthy controls, were enrolled in this meta-analysis. The results of the meta-analysis showed that serum levels of NSE and S-100β in ACI patients were significantly higher than the control group. Subgroup analysis based on ethnicity revealed that the serum levels of NSE and S-100β in ACI patients were significantly higher than the control group in Asian population. In Caucasian population, the serum levels of NSE in case group was significantly higher than the control group, but no significant differences in serum levels of S-100β were observed between ACI patients and the control group.

CONCLUSIONS

Based on our results, we conclude that serum levels of NSE and S-100β strongly correlate with ACI in Asian population, and may be important clinical markers for diagnosis and treatment of ACI.

Predictive value of neuromarkers supported by a set of clinical criteria in patients with mild traumatic brain injury: S100B protein and neuron-specific enolase on trial

Object

The role of the neuromarkers S100B protein and neuron-specific enolase (NSE) in minor head injury is well established. Moreover, there are sensitive decision rules available in the literature to identify clinically important brain lesions. However, it is not clear if using the biomarkers has an influence on the predictability of the decision rule. The purpose of this study was to determine if a set of preclinical and clinical parameters combined with 2 neuromarker levels could serve as reliable guidance for accurate diagnosis.

Methods

Prospective evaluation of a cohort of head trauma patients with Glasgow Coma Scale scores of 13–15 was performed at an academic, Level I trauma center. Blood samples and cranial CT studies were obtained for all patients within 3 hours after injury. The hypothesis of the study was whether the combination of an increase of S100B and NSE levels in serum and other defined risk factors are associated with a pathological finding on CT. A forward stepwise logistic regression model was used.

Results

The study included 107 head trauma patients with a mean age of 59 ± 23 years. Twenty-five patients (23.4%) had traumatic lesions on CT. Eight patients underwent craniotomy. The analysis provided a model with good overall accuracy for discriminating cases with clinically important brain injury, including the 6 variables of S100B, NSE, nausea, amnesia, vomiting, and loss of consciousness. The area under the curve (AUC) was 0.88 (0.83–0.93). The receiver operating characteristic curve plots detecting clinically important brain injury for the single variables of S100B and NSE showed an AUC of 0.63 and 0.64, respectively.

Conclusions

The integration of the neuromarker panel as part of a diagnostic rule including the high-risk factors of nausea, vomiting, amnesia, and loss of consciousness is safe and reliable in determining a diagnosis, pending the availability of more brain-specific neuromarkers. Clinical trial registration no.: NCT00622778 (ClinicalTrials.gov).

Evaluation and management of mild traumatic brain injury: an Eastern Association for the Surgery of Trauma practice management guideline

BACKGROUND

An estimated 1.1 million people sustain a mild traumatic brain injury (MTBI) annually in the United States. The natural history of MTBI remains poorly characterized, and its optimal clinical management is unclear. The Eastern Association for the Surgery of Trauma had previously published a set of practice management guidelines for MTBI in 2001. The purpose of this review was to update these guidelines to reflect the literature published since that time.

METHODS

The PubMed and Cochrane Library databases were searched for articles related to MTBI published between 1998 and 2011. Selected older references were also examined.

RESULTS

A total of 112 articles were reviewed and used to construct a series of recommendations.

CONCLUSION

The previous recommendation that brain computed tomographic (CT) should be performed on patients that present acutely with suspected brain trauma remains unchanged. A number of additional recommendations were added. Standardized criteria that may be used to determine which patients receive a brain CT in resource-limited environments are described. Patients with an MTBI and negative brain CT result may be discharged from the emergency department if they have no other injuries or issues requiring admission. Patients taking warfarin who present with an MTBI should have their international normalized ratio (INR) level determined, and those with supratherapeutic INR values should be admitted for observation. Deficits in cognition and memory usually resolve within 1 month but may persist for longer periods in 20% to 40% of cases. Routine use of magnetic resonance imaging, positron emission tomography, nuclear magnetic resonance, or biochemical markers for the clinical management of MTBI is not supported at the present time.

Alcohol and the head-injured patient

Alcohol intoxication is a major predisposing factor for trauma in general and head injury in particular. The management of the head-injured patient is highly contingent on the accurate assessment of this patient’s consciousness, which is invariably impaired if the patient is intoxicated. This complicates the decision-making process and impedes the promptness needed in management when the head injury is severe. Furthermore, the prognosis of the head injury can depend on the patient’s degree and pattern of intoxication. This article presents some of the latest epidemiological data about the association of alcohol and head injury. It also highlights some of the challenges posed by alcohol intoxication in the management of head-injured patients, and examines the importance of documenting intoxication in head-injured patients.