The Clinical Significance Of Serum UCH-L1 And GFAP In Premature Infants With Brain Injury

ObjectiveTo investigate the relationship between brain injury and serum ubiquitin carboxy-terminal hydrolase L1(UCH-L1)and glial fibrillary acidic protein(GFAP)in preterm infants,analyze its clinical significance in premature infants with brain injury.MethodsPremature infants with gestational age less than 34 weeks were selected from August 2014 to October 2016.Blood samples were obtained at 6 h and 72 h after birth,the serum levels of UCH-L1 and GFAP were detected by enzyme linked immuno sorbent assay(ELISA).According to the results of craniocerebral imaging,all infants were divided into white matter damage(WMD)group,periventricular-intraventri cular haemorrhage(PVH-IVH)group and no brain injury group.According to the degree of brain injury,WMD group and PVH-IVH group were divided into mild and severe brain injury group.The Gesell developmental diagnostic scale was used to evaluate the developmental quotient of premature infants with brain injury,and according to the results of the developmental quotient at correction of gestational age6 months,the children with brain injury were divided into good prognosis group and poor prognosis group.Then the comparisons of serum UCH-L1 and GFAP levels in preterm infants between three groups(no brain injury group,PVH-IVH group and WMD group),mild and severe brain injury group,good prognosis group and poor prognosis group were implemented,to finding out their differences,and analyzing the early predictive value of serum UCH-L1 and GFAP in premature brain injury and its correlation with nerve prognosis.Results(1)At 6 h and 72 h after birth,the serum levels of UCH-L1 and GFAP in WMD group were significantly higher than those in the PVH-IVH group and no brain injury group,and PVH-IVH group was significantly higher than no brain injury group,the differences were significant(P<0.05).Compare at different time points in the same group,the levels of serum UCH-L1 in the PVH-IVH group and WMD group at 72 h after birth were significantly lower than those at 6 h after birth,and the levels ofserum GFAP at 72 h after birth were significantly higher than those at 6 h after birth,the differences were significant(P <0.05).In no brain injury group,there was no significant difference in serum UCH-L1 and GFAP levels between 6 h and 72 h after birth(P>0.05).(2)At each time point,the serum UCH-L1 and GFAP levels in the severe WMD group were significantly higher than those in the mild WMD group,and severe PVH-IVH group was significantly higher than mild PVH-IVH group,the differences were significant(P<0.05).(3)Follow up WMD and PVH-IVH children to correction of gestational age 6months,32 cases were followed up,7 of them had poor prognosis,and 25 had good prognosis.The serum GFAP levels at 6 h and 72 h after birth were significantly higher in poor prognosis group than those in the good prognosis group(P<0.05).The serum UCH-L1 level at 6 h after birth was significantly higher in poor prognosis group than that in the good prognosis group(P < 0.05),there was no significant difference between the 2 groups in serum UCH-L1 levels at 72 h after birth(P>0.05).(4)With 0.57 ng/mL as a truncated value,the sensitivity of serum UCH-L1 at 6 h after birth in predicting premature brain injury was 84%,the specificity was 87.5%.With 0.51 ng/mL as a truncated value,the sensitivity of serum GFAP at 6 h after birth was 79% and the specificity was 74%.(5)Correlation analysis showed that,at 6 h after birth,the serum UCH-L1 and GFAP levels were negatively correlated with the prognosis(r=-0.68,-0.69 respecti vely,P<0.01).At 72 h after birth,the serum GFAP level was negatively correlated with the prognosis(r=-0.79,P<0.01),and there was no significant correlation between serum UCH-L1 level and the prognosis of the children(r =-0.26,P > 0.05).ConclusionsSerum UCH-L1 and GFAP can be used as early sensitive biomarkers in evaluating brain injury in preterm infants,detecting the changes of serum UCH-L1 and GFAP levels in preterm infants with brain injury is helpful in judging the severity of brain injury and assessing prognosis.