Application Of Activin A And AEEG In The Early Diagnosis Of Brain Injury In Premature Infants

BackgroundApproximately 15 million infants are born prematurely each year worldwide.In China,the birth rate of preterm infants is about 8%,making it the second most premature country in the world after India.Although perinatal medical technology has been improved,some survivors still suffer from brain injury and developmental disabilities.The imaging examination alone cannot be used to diagnose or evaluate brain injury in preterm infants at an early stage because there are no specific clinical manifestations.As a result,predicting the occurrence of brain injuries in preterm infants at an early stage is not only a medical concern,but also a public-health issue.ObjectiveThe purpose of this study was to investigate the value of serum activin A level combined with amplitude-integrated electroencephalography(a EEG)in the early detection of brain injury in preterm babies.MethodsPreterm infants in Neonatal Intensive Care Unit(NICU)of our hospital from May 2020 to May 2022 were enrolled in the present study.Participants met the following criteria simultaneously: gestational age 32 ～ 34 weeks,birth weight ≤2000g.According to the "Expert Consensus on the Diagnosis,Prevention and Treatment of Brain Injury in Preterm Infants",which was published by Chinese Medical Doctor Association’s in 2012,we assessed the craniocerebral ultrasound,brainstem auditory evoked potentials(BAEP)or magnetic resonance imaging(MRI)of infants within a week of birth.Based on the results,the preterm infants were divided into four groups:hemorrhagic injury group,non-hemorrhagic injury group,abnormal brainstem auditory evoked potential group(premature infants with brain injury related risk factors and clinical manifestations,without abnormality of imaging examination)and control group(premature infants without brain injury related risk factors,clinical manifestations,or abnormal subsidiary exams).Therein,patients with brain injury with mild(grade 1 or 2)hemorrhage,or(and)abnormal BAEP but non-hemorrhage were included in the non-hemorrhagic injury group.Contrarily,Patients who had both hemorrhagic injury and BAEP abnormalities were included in the hemorrhagic brain injury group.As long as the patients develop severe hemorrhage(grade 3 or 4),they were considered as hemorrhagic injury group.The serum level of activin A were assessed within 6 hours of birth,and the brain function was monitored(the duration of monitoring should be at least four to six hours)within 6 days of birth.a EEG scores were calculated based on the results of the amplitude-integration analysis.Results1.Ninety preterm infants were finally enrolled in the study,including 9 in hemorrhagic injury group,13 in non-hemorrhagic injury group,31 in abnormal BAEP group,and 37 in control group.2.There were no significant differences in the overall data(gender,gestational age,birth weight,delivery mode,etc.)among the four groups(P>0.05).3.The median a EEG scores of hemorrhagic brain injury group,non-hemorrhagic brain injury group,BAEP abnormal group and control group were 9,5,11,and 13 respectively.In the meantime,the median serum activin A levels were24.30 ng/ml,30.50 ng/ml,24.39 ng/ml and 19.56 ng/ml respectively.a EEG scores of hemorrhagic brain injury group,non-hemorrhagic brain injury group and abnormal BAEP group were lower than no-brain injury group(control group)(P<0.01).The activin A levels of the above three groups were higher than control group(P<0.01).However,there was no significant difference among hemorrhagic brain injury group,non-hemorrhagic brain injury group and abnormal BAEP group either activin A or a EEG scores(P>0.05).4.Linear regression analysis revealed that the activin A level is negatively correlated with a EEG scores(r = 0.566,P < 0.001).5.Based on the ROC curve,the area under the curve for the a EEG score,serum activin A level,and the combination of a EEG score and serum activin A level was0.896,0.850,and 0.935,respectively;the sensitivity was 0.943,0.868,and 0.830,respectively.Conclusions1.Serum activin A level could serve as an indicator for early diagnosis of brain injury in preterm infants.2.a EEG has high sensitivity and superior diagnostic value for early brain injury in preterm infants.3.Relative to use of either indicator alone,a combination of activin A and a EEG score have higher sensitivity and specificity diagnostic values for brain injury in preterm infants.