Special considerations in infants and children

Head injury in children is one of the most common causes of death and disability in the US and, increasingly, worldwide. This chapter reviews the causes, patterns, pathophysiology, and treatment of head injury in children across the age spectrum, and compares pediatric head injury to that in adults. Classification of head injury in children can be organized according to severity, pathoanatomic type, or mechanism. Response to injury and repair mechanisms appear to vary at different ages, and these may influence optimal treatment; however, much work is still needed before investigation leads to clearly effective clinical interventions. This is true both for the more severe injuries as well as those at the milder end of the injury spectrum, the latter of which have received increasing attention. In this chapter, neuroassessment tools for each age, newer imaging modalities including magnetic resonance imaging (MRI), and specific pediatric management issues, including intracranial pressure (ICP) monitoring and seizure prophylaxis, are reviewed. Finally, specific head injury patterns and functional outcomes relevant to pediatric patients are discussed. While head injury is common, the number of head-injured children is significantly smaller than the corresponding adult head-injured population. When divided further by specific ages, injury types, and other sources of heterogeneity, properly powered clinical research is likely to require large data sets that will allow for stratification across variables, including age. While much has been learned in the past several decades, further study will be required to determine the best management practices for optimizing recovery in individual pediatric patients. This approach is likely to depend on collaborative international head injury databases that will allow researchers to better understand the nuanced evolution of different types of head injury in patients at each age, and the pathophysiologic, treatment-related, and genetic factors that influence recovery.

Apolipoprotein E genotype and traumatic brain injury in children--association with neurological outcome

OBJECTIVE

To determine whether the presence of Apolipoprotein E epsilon4 genotype (ApoE epsilon4) is associated with outcomes of traumatic brain injury in children.

MATERIALS AND METHODS

The ApoE genotype was examined in the group of 70 pediatric patients who suffered from traumatic brain injury. The group consists of 48 boys and 22 girls, and the most frequent was the E3 isoform of ApoE. Polymerase chain reaction/restriction fragment length polymorphism method was used for the ApoE genotype assessment. The severity of trauma was assessed by Glasgow Coma Scale and graded into three categories. The presence of focal neurology signs, comparing the admission and dimission status, and duration of hospital care were observed. The neurological outcome after 1 year was assessed by Glasgow Outcome Scale. Trauma severity was compared with the neurological outcome, according to different ApoE genotypes. For statistical processing, t test, nonparametric Wilcoxon test, Fisher, and chi(2) tests were used.

CONCLUSION

Our results suggest the association between the ApoE genotype and outcome of traumatic brain injury in children. Patients with ApoE epsilon4 genotype were more likely to have severe clinical symptomatology and unfavorable neurological outcome after traumatic brain injury compared to significantly better outcome with other ApoE genotype.

Apolipoprotein E polymorphism and outcome after closed traumatic brain injury: influence of ethnic and regional differences

OBJECT

The presence of the apolipoprotein E-epsilon4 (APOE-epsilon4) allele is reported to be associated with poor outcome after traumatic brain injury (TBI). This study was performed to determine if the presence of the APOE-epsilon4 allele influenced outcome in a cohort of black patients with TBI who had homogeneous neuropathological findings.

METHODS

Venous blood was collected at the time of admission to determine the APOE genotype in black Zulu-speaking patients who presented with traumatic cerebral contusions. The frequency of the APOE-epsilon4 allele's appearance was correlated with outcome at a minimum of 6 months of follow up. Univariate and multivariate analyses were performed to determine independent risk factors and to control for confounding factors. In 110 black Zulu-speaking patients with traumatic cerebral contusions, genotypes for APOE were analyzed. Eleven of 45 (24.4%) with the APOE-epsilon4 allele experienced a poor outcome, compared with 10 (15.4%) of 65 without this allele (p = 0.34). Both patients with homozygous APOE-epsilon4 alleles experienced a good outcome (Glasgow Outcome Score 5). Univariate and multivariate analysis revealed no significant relationship in patients with the APOE-epsilon4 allele with regard to age, admission Glasgow Comas Scale score, contusion volume, type of neurosurgical management, and outcome. The risk of a poor outcome was, however, greater in patients with the APOE-epsilon4 allele (relative risk 1.59; 95% confidence interval 0.74-3.42).

CONCLUSIONS

The authors recorded no relationship between APOE-epsilon4 allele status and outcome after TBI in black patients. Given the high regional susceptibility to the APOE gene, further studies, possibly even community-based investigations and studies conducted in other geographic areas, are probably warranted.